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The supraspinatus tendon is composed of 5 different layers consisting of intertwining bundles. On a front portion of the tendon, the layers become coated bundles which insert on the trochanter. At the insertion, the superficial or bursal surface of the tendon corresponding to the tendon fibers in contact with the subacromial bursa can be distinguished from the deep surface corresponding to the fibers in contact with the glenohumeral joint. A tendon tear may involve partial or total disruption of the tendon fibers and is called full-thickness tear if it affects the entire tendon, and partial-thickness tear if it involves only part of the tendon. Partial-thickness tears of the supraspinatus tendon include lesions of the superficial, deep and central surface or tendon delamination. A contrast enhanced examination requires injection of contrast agent into the joint (arthrography followed by computed tomography (CT) or magnetic resonance imaging (MRI)) to study the deep surface, and injection into the subacromial bursa (bursography followed by CT) to study the superficial surface. MRI and ultrasound (US) examination allow the study of these different tendon layers without the use of contrast agent (which is not possible at CT). PMID:23396264
Guerini, H.; Fermand, M.; Godefroy, D.; Feydy, A.; Chevrot, A.; Morvan, G.; Gault, N.; Drap�, J.L.
The supraspinatus tendon is composed of 5 different layers consisting of intertwining bundles. On a front portion of the tendon, the layers become coated bundles which insert on the trochanter. At the insertion, the superficial or bursal surface of the tendon corresponding to the tendon fibers in contact with the subacromial bursa can be distinguished from the deep surface corresponding to the fibers in contact with the glenohumeral joint. A tendon tear may involve partial or total disruption of the tendon fibers and is called full-thickness tear if it affects the entire tendon, and partial-thickness tear if it involves only part of the tendon. Partial-thickness tears of the supraspinatus tendon include lesions of the superficial, deep and central surface or tendon delamination.A contrast enhanced examination requires injection of contrast agent into the joint (arthrography followed by computed tomography (CT) or magnetic resonance imaging (MRI)) to study the deep surface, and injection into the subacromial bursa (bursography followed by CT) to study the superficial surface. MRI and ultrasound (US) examination allow the study of these different tendon layers without the use of contrast agent (which is not possible at CT). PMID:23396264
Guerini, H; Fermand, M; Godefroy, D; Feydy, A; Chevrot, A; Morvan, G; Gault, N; Drap�, J L
Partial-thickness articular surface supraspinatus tears: a new transtendon suture technique.
The standard technique for repairing partial-thickness tears of the supraspinatus tendon includes completion of the lesion to a full-thickness tear. Partial articular-side supraspinatus tendon avulsions (PASTA) form a subgroup deserving special consideration. We present a transtendon suture technique that is able to preserve the intact tendon fibers and to achieve firm attachment of the tendon to the humeral footprint using 1 double-loaded bone anchor. The surgical technique is described in detail, and pitfalls and complications are noted. The clinical results of the first 22 consecutive patients are reported, showing an increase in the UCLA score from 17.1 to 31.2 points and a patient satisfaction rate of 91%. PMID:15756195
Waibl, Bernhard; Buess, Eduard
Endoscopic transtendinous repair for partial-thickness proximal hamstring tendon tears.
Partial tears of the proximal hamstring tendon can successfully be managed with tendon repair in cases of failed conservative management. As in partial-thickness gluteus medius repair, a transtendinous technique can be used to repair partial-thickness undersurface tears of the hamstring origin. This report details an endoscopic transtendinous approach for the treatment of partial-thickness hamstring tendon tears. PMID:24749032
Jackson, Timothy J; Trenga, Anthony; Lindner, Dror; El-Bitar, Youseff; Domb, Benjamin G
Endoscopic Transtendinous Repair for Partial-Thickness Proximal Hamstring Tendon Tears
Partial tears of the proximal hamstring tendon can successfully be managed with tendon repair in cases of failed conservative management. As in partial-thickness gluteus medius repair, a transtendinous technique can be used to repair partial-thickness undersurface tears of the hamstring origin. This report details an endoscopic transtendinous approach for the treatment of partial-thickness hamstring tendon tears. PMID:24749032
Jackson, Timothy J.; Trenga, Anthony; Lindner, Dror; El-Bitar, Youseff; Domb, Benjamin G.
Functional morphology of the supraspinatus tendon.
Grossly normal supraspinatus tendons were analyzed by stereomicroscope dissection and three-dimensional serial-section reconstruction. Four structurally independent subunits were identified: the tendon proper extended from the musculotendinous junction to approximately 2.0 cm medial to the greater tuberosity. It was composed of parallel collagen fascicles oriented along the tensional axis and separated by a prominent endotenon region. There was no interdigitation of fascicles, and an 18% incidence of fascicle convergence as the fascicles coursed from muscle toward greater tuberosity. The attachment fibrocartilage extended from the tendon proper to the greater tuberosity, consisted of a complex basket-weave of collagen fibers, and stained diffusely with alcian blue. The densely packed unidirectional collagen fibers of the rotator cable extended from the coracohumeral (CH) ligament posteriorly to the infraspinatus, coursing both superficial and deep to the tendon proper. The capsule was composed of thin collagen sheets each with uniform fiber alignment that differed slightly between sheets. These data describe a specialized tendon capable of internally compensating for changing joint angles through fascicles which are structurally independent and can slide past one another. The tendon attachment exhibits a structure adapted to tensional load dispersion and resistance to compression. PMID:12382954
Fallon, Jonathan; Blevins, Field T; Vogel, Kathryn; Trotter, John
Detection of partial-thickness tears in ligaments and tendons by Stokes-polarimetry imaging
NASA Astrophysics Data System (ADS)
A Stokes polarimetry imaging (SPI) system utilizes an algorithm developed to construct degree of polarization (DoP) image maps from linearly polarized light illumination. Partial-thickness tears of turkey tendons were imaged by the SPI system in order to examine the feasibility of the system to detect partial-thickness rotator cuff tear or general tendon pathology. The rotating incident polarization angle (IPA) for the linearly polarized light provides a way to analyze different tissue types which may be sensitive to IPA variations. Degree of linear polarization (DoLP) images revealed collagen fiber structure, related to partial-thickness tears, better than standard intensity images. DoLP images also revealed structural changes in tears that are related to the tendon load. DoLP images with red-wavelength-filtered incident light may show tears and related organization of collagen fiber structure at a greater depth from the tendon surface. Degree of circular polarization (DoCP) images exhibited well the horizontal fiber orientation that is not parallel to the vertically aligned collagen fibers of the tendon. The SPI system's DOLP images reveal alterations in tendons and ligaments, which have a tissue matrix consisting largely of collagen, better than intensity images. All polarized images showed modulated intensity as the IPA was varied. The optimal detection of the partial-thickness tendon tears at a certain IPA was observed. The SPI system with varying IPA and spectral information can improve the detection of partial-thickness rotator cuff tears by higher visibility of fiber orientations and thereby improve diagnosis and treatment of tendon related injuries.
Kim, Jihoon; John, Raheel; Walsh, Joseph T.
Objectives The effects of disease progression and common tendinopathy treatments on the tissue characteristics of human rotator cuff tendons have not previously been evaluated in detail owing to a lack of suitable sampling techniques. This study evaluated the structural characteristics of torn human supraspinatus tendons across the full disease spectrum, and the short-term effects of subacromial corticosteroid injections (SCIs) and subacromial decompression (SAD) surgery on these structural characteristics. Methods Samples were collected inter-operatively from supraspinatus tendons containing small, medium, large and massive full thickness tears (n = 33). Using a novel minimally invasive biopsy technique, paired samples were also collected from supraspinatus tendons containing partial thickness tears either before and seven weeks after subacromial SCI (n = 11), or before and seven weeks after SAD surgery (n = 14). Macroscopically normal subscapularis tendons of older patients (n = 5, mean age = 74.6 years) and supraspinatus tendons of younger patients (n = 16, mean age = 23.3) served as controls. Ultra- and micro-structural characteristics were assessed using atomic force microscopy and polarised light microscopy respectively. Results Significant structural differences existed between torn and control groups. Differences were identifiable early in the disease spectrum, and increased with increasing tear size. Neither SCI nor SAD surgery altered the structural properties of partially torn tendons seven weeks after treatment. Conclusions These findings may suggest the need for early clinical intervention strategies for torn rotator cuff tendons in order to prevent further degeneration of the tissue as tear size increases. Further work is required to establish the long-term abilities of SCI and SAD to prevent, and even reverse, such degeneration. Cite this article: Bone Joint Res 2014;3:252�61. PMID:25106417
Tilley, J. M. R.; Murphy, R. J.; Chaudhury, S.; Czernuszka, J. T.; Carr, A. J.
Work-related lesions of the supraspinatus tendon: a case�control study
Objectives��To examine the dose�response relationship between cumulative duration of work with highly elevated arms (work above shoulder\\u000a level) as well as of manual material handling and ruptures of the supraspinatus tendon in a population-based case�control\\u000a study.\\u000a \\u000a \\u000a \\u000a \\u000a Methods��In 14 radiologic practices, we recruited 483 male patients aged 25�65 with radiographically confirmed partial (n�=�385) or total (n�=�98) supraspinatus tears associated with shoulder
Andreas Seidler; Ulrich Bolm-Audorff; Gabriela Petereit-Haack; Elke Ball; Magdalena Klupp; No�lle Krauss; Gine Elsner
In situ fibril stretch and sliding is location-dependent in mouse supraspinatus tendons.
Tendons are able to transmit high loads efficiently due to their finely optimized hierarchical collagen structure. Two mechanisms by which tendons respond to load are collagen fibril sliding and deformation (stretch). Although many studies have demonstrated that regional variations in tendon structure, composition, and organization contribute to the full tendon?s mechanical response, the location-dependent response to loading at the fibril level has not been investigated. In addition, the instantaneous response of fibrils to loading, which is clinically relevant for repetitive stretch or fatigue injuries, has also not been studied. Therefore, the purpose of this study was to quantify the instantaneous response of collagen fibrils throughout a mechanical loading protocol, both in the insertion site and in the midsubstance of the mouse supraspinatus tendon. Utilizing a novel atomic force microscopy-based imaging technique, tendons at various strain levels were directly visualized and analyzed for changes in fibril d-period with increasing tendon strain. At the insertion site, d-period significantly increased from 0% to 1% tendon strain, increased again from 3% to 5% strain, and decreased after 5% strain. At the midsubstance, d-period increased from 0% to 1% strain and then decreased after 7% strain. In addition, fibril d-period heterogeneity (fibril sliding) was present, primarily at 3% strain with a large majority occurring in the tendon midsubstance. This study builds upon previous work by adding information on the instantaneous and regional-dependent fibrillar response to mechanical loading and presents data proposing that collagen fibril sliding and stretch are directly related to tissue organization and function. PMID:25468300
Connizzo, Brianne K; Sarver, Joseph J; Han, Lin; Soslowsky, Louis J
OBJECTIVES�To investigate age related and site specific variations in turnover and chemistry of the collagen network in healthy tendons as well as the role of collagen remodelling in the degeneration of the supraspinatus tendon (ST-D) in rotator cuff tendinitis.?METHODS�Collagen content and the amount of hydroxylysine (Hyl), hydroxylysylpyridinoline (HP), lysylpyridinoline (LP), and the degree of non-enzymatic glycation (pentosidine) were investigated in ST-D and in normal human supraspinatus (ST-N) and biceps brachii tendons (BT-N) by high-performance liquid chromatography.?RESULTS�In BT-N, tendons that served as control tissue as it shows rarely matrix abnormalities, pentosidine levels rise linearly with age (20-90 years), indicating little tissue remodelling (resulting in an undisturbed accumulation of pentosidine). A similar accumulation was observed in ST-N up to 50�years. At older ages, little pentosidine accumulation was observed and pentosidine levels showed large interindividual variability. This was interpreted as remodelling of collagen in normal ST after age 50�years because of microruptures (thus diluting old collagen with newly synthesised collagen). All degenerate ST samples showed decreased pentosidine levels compared with age matched controls, indicating extensive remodelling in an attempt to repair the tendon defect. Collagen content and the amount of Hyl, HP, and LP of ST-N and BT-N did not change with age. With the exception of collagen content, which did not differ, all parameters were significantly (p<0.001) lower in BT-N. The ST-D samples had a reduced collagen content and had higher Hyl, HP, and LP levels than ST-N (p<0.001).?CONCLUSIONS�Inasmuch as Hyl, HP, and LP levels in ST-N did not change with age, tissue remodelling as a consequence of microruptures does not seem to affect the quality of the tendon collagen. On the other hand, the clearly different profile of post-translational modifications in ST-D indicates that the newly deposited collagen network in degenerated tendons is qualitatively different. It is concluded that in ST-D the previously functional and carefully constructed matrix is replaced by aberrant collagen. This may result in a mechanically less stable tendon; as the supraspinatus is constantly subjected to considerable forces this could explain why tendinitis is mostly of a chronic nature.?? Keywords: collagen; tendons; crosslinks; pentosidine PMID:10343538
Bank, R.; TeKoppele, J.; Oostingh, G.; Hazleman, B.; Riley, G.
Rotator cuff tears are common conditions that can alter shoulder mechanics and may lead to damage of intact joint tissues. These injuries are of particular concern in populations who perform tasks requiring repetitive overhead activity (e.g., athletes and laborers) and who are likely to return to aggressive pre-injury activity levels despite limited understanding of the potentially damaging effects on the remaining tissues. Therefore, we investigated the effect of returning to overuse activity following a supraspinatus tear on shoulder function and the mechanical properties of the remaining intact tendons and glenoid cartilage. Forty rats underwent 4 weeks of overuse activity to create a tendinopathic condition followed by detachment of the supraspinatus tendon and were then randomized into two groups: continued overuse or cage activity. Ambulatory measurements were performed throughout the 8 weeks prior to euthaniasia, and properties of the adjacent tendons and cartilage were evaluated. Results demonstrated that shoulder function was not compromised in the return to overuse group. However, alterations of the glenoid cartilage and biceps tendon properties occurred. Our results help define the contributory roles of common mechanical injury mechanisms and provide a framework by which physicians could better prescribe long-term treatment strategies for patients. PMID:23280495
Reuther, Katherine E.; Thomas, Stephen J.; Sarver, Joseph J.; Tucker, Jennica J.; Lee, Chang-Soo; Gray, Chancellor F.; Glaser, David L.; Soslowsky, Louis J.
We report the use of the double-pulley technique for arthroscopic fixation of the bony PASTA (partial articular surface tendon avulsion) lesion. Arthroscopic examination documented a 15-mm-long and 8-mm-wide comminuted bony avulsion with 2 main fragments. Two double-loaded suture anchors were placed with a transtendinous technique at the anterior and posterior edges of the lesion respecting the tendon insertion to the avulsed fragment. The medial sutures were retrieved through the intact supraspinatus tendon medially to the fracture. The sutures were initially coupled in a double-pulley configuration generating 2 sutures oriented from anterior to posterior; then a simple suture for each anchor oriented from medial to lateral was obtained. At the end of the procedure, the adequacy of reduction and stability of the fragments were confirmed. At 2 months from surgery, radiographic healing of the fracture was noted and integrity of the supraspinatus tendon insertion to the footprint was confirmed by arthro�magnetic resonance imaging, with full recovery of daily activities and complete active range of motion confirmed at 6 and 12 months. The double-pulley technique allows optimal reduction of bony fragments and reconstruction of normal footprint anatomy even in comminuted fractures. Moreover, it creates a waterproof reduction of the fragments, protecting the fracture site from synovial fluid. PMID:23767005
Murena, Luigi; Canton, Gianluca; Falvo, Daniele A.; Genovese, Eugenio A.; Surace, Michele F.; Cherubino, Paolo
Articular-surface partial-thickness rotator cuff tears play a significant role in shoulder pathology, but the role of the articular-surface tissue is poorly understood. This investigation assessed the effect of an articular-surface partial-thickness rotator cuff tear on intratendinous strain fields. A magnetic resonance imaging�based technique quantified intratendinous strains in healthy cadaveric shoulders at 15�, 30�, 45�, and 60� of glenohumeral abduction. A
Michael J Bey; Matthew L Ramsey; Louis J Soslowsky
Shoulders with supraspinatus (SSP) tears are associated with significantly larger critical shoulder angles (CSA) compared to disease-free shoulders. We hypothesized that larger CSAs increase the ratio of joint shear to joint compression forces (defined as "instability ratio"), requiring substantially increased compensatory supraspinatus loads. A shoulder simulator with simulated deltoid, supraspinatus, infraspinatus/teres minor, and subscapularis musculotendinous units was constructed. The model was configured to represent either a normal CSA of 33� or a CSA characteristic of shoulders with rotator cuff tears (38�), and the components of the joint forces were measured. The instability ratio increased for the 38� CSA compared with the control CSA (33�) for a range of motion between 6� to 61� of thoracohumeral abduction with the largest differences in instability observed between 33� and 37� of elevation. In this range, SSP force had to be increased by 13-33% (15-23?N) to stabilize the arm in space. Our results support the concept that a high CSA can induce SSP overload particularly at low degrees of active abduction. PMID:24700399
Gerber, Christian; Snedeker, Jess G; Baumgartner, Daniel; Vieh�fer, Arnd F
Supraspinatus rupture at the musculotendinous junction in a young woman.
The vast majority of rotator cuff tears occur within the tendon or as an avulsion from the greater tuberosity. Supraspinatus injury at the musculotendinous junction is a very uncommon event. We describe a case of supraspinatus rupture at the musculotendinous junction, with successful conservative treatment. It occurred in a 23-year-old woman, the youngest patient with this uncommon type of injury. To our knowledge, this is the first case of rupture of the supraspinatus muscle at the musculotendinous junction in a young woman and the second in a woman. PMID:24292386
Benazzo, Francesco; Marullo, Matteo; Pietrobono, Luigi
... References: Ackermann PW, Renstrom P. Tendinopathy in sport. Sports Health. May 2012;4(3):193-201. Sharma P, Maffulli N. Tendon injury and tendinopathy: healing and repair. J Bone Joint Surg . 2005;87A:187-202. TENDONITIS Sports Tips are brought to you by the American ...
The behavior of rotator cuff tendon cells in three-dimensional culture
The rotator cuff is composed of the supraspinatus, infraspinatus, subcapularis, and teres minor tendons. Rotator cuff injuries are common athletic and occupational injuries that surgery cannot fully repair. Therefore tendon ...
Gill, Harmeet (Harmeet Kaur)
Tendinopathy and small partial-thickness tears of the rotator cuff tendon are common presentations in sports medicine. No promising treatment has yet been established. Corticosteroid injections may improve symptoms in the short term but do not primarily treat the tendon pathology. Ultrasound-guided autologous tenocyte implantation (ATI) is a novel bioengineered treatment approach for treating tendinopathy. We report the first clinical case of ATI in a 20-year-old elite gymnast with a rotator cuff tendon injury. The patient presented with 12?months of increasing pain during gymnastics being unable to perform most skills. At 1?year after ATI the patient reported substantial improvement of clinical symptoms. Pretreatment and follow-up MRIs were reported and scored independently by two experienced musculoskeletal radiologists. Tendinopathy was improved and the partial-thickness tear healed on 3?T MRI. The patient was able to return to national-level competition. PMID:23314880
Wang, Allan W; Bauer, Stefan; Goonatillake, Matthew; Breidahl, William; Zheng, Ming-Hao
Muscle architecture of biceps brachii, triceps brachii and supraspinatus in the horse
Three muscles from the proximal equine forelimb were dissected in order to investigate their potential to contribute to proximal limb mechanics. Muscle mass, fibre length, tendon mass and tendon length were measured from biceps brachii, triceps brachii, supraspinatus and lacertus fibrosus (biceps lateral head mass 171�343.4 g and fibre length 0.5�0.8 cm; biceps medial head mass 283�500 g and fibre length 2.2�4 cm; biceps tendon mass 121.8�260 g and tendon length 35�44 cm; triceps long head mass 3200�6663 g and fibre length 19�26.3 cm; triceps lateral head mass 513.8�1240 g and fibre length 17.5�24 cm; triceps medial head mass 85.2�270.6 g and fibre length 9�16.8 cm; supraspinatus mass 793�1546 g and fibre length 4.7�12.4 cm; lacertus fibrosus mass 4.6�12.4 g and length 10�16 cm). Physiological cross-sectional area (PCSA) and maximum isometric force were estimated for each muscle, and moment arm measurements were taken at the shoulder and elbow joints. Biceps has a greater isometric force-generating capacity than supraspinatus. It also appears to have a larger shoulder moment arm, so could therefore have the potential to make a greater contribution to the shoulder moment than supraspinatus. Supraspinatus is likely to function primarily as a shoulder stabilizer rather than a shoulder extensor. Biceps also functions as an elbow flexor and data here indicate that it has a greater PCSA and isometric force-generating capacity than its antagonist triceps brachii. Calculation of tendon forces showed that the biceps tendon can withstand much greater forces than lacertus fibrosus. This study will enable further investigation into the interaction between energy recycling in elastic tissues and the generation and absorption of mechanical work by adjacent muscle groups in the equine forelimb. PMID:17229281
Watson, J C; Wilson, A M
Plasticity of Muscle Architecture After Acute Supraspinatus Tear
Study Design Controlled Laboratory Study Objectives To measure the architectural properties of rat supraspinatus muscle after a complete detachment of its distal tendon. Methods Supraspinatus muscles were released from the left humerus of 29 rats (Sprague-Dawley, mass 400 - 450 g) and animals were returned to cage activity for 2 weeks (n = 12), 4 weeks (n = 9), or 9 weeks (n=8) before euthanasia. Measurements of muscle mass, pennation angle, fiber bundle length (sarcomere number), and sarcomere length permitted calculation of normalized fiber length, serial sarcomere number, and physiological cross-sectional area (PCSA). Results Coronal oblique sections of the supraspinatus confirmed surgical transection of the supraspinatus muscle at 2 weeks, with reattachment by 4 weeks. Muscle mass and length were significantly lower in released muscles at 2 weeks, 4 weeks, and 9 weeks. Sarcomere lengths in released muscles were significantly shorter at 2 weeks but not different by 4 weeks. Sarcomere number was significantly reduced at 2 and 4 weeks, but returned to control values by 9 weeks. The opposing effects of smaller mass and shorter fibers produced significantly smaller PCSA at 2 weeks, but PCSA returned to control levels by 4 weeks. Conclusions Release of the supraspinatus muscle produced early radial and longitudinal atrophy of the muscle. The functional implications of these adaptations would be most profound at early time points (particularly relevant for rehabilitation), when the muscle remains smaller in cross-sectional area and, due to reduced sarcomere number, would be forced to operate over a wider range of the length-tension curve and at higher velocities, all adaptations resulting in compromised force generating capacity. These data are relevant to physical therapy because they provide tissue-level insights into impaired muscle and shoulder function following rotator cuff injury. PMID:20710096
Ward, Samuel R.; Sarver, Joseph J.; Eng, Carolyn M.; Kwan, Alan; W�rgler-Hauri, Carola C.; Perry, Stephanie M.; Williams, Gerald R.; Soslowsky, Louis J.; Lieber, Richard L.
... told Kim she had Achilles tendonitis. What Is Achilles Tendonitis and Who Gets It? Your Achilles tendon is ... very painful. Continue What Are the Symptoms of Achilles Tendonitis? Most cases of Achilles tendonitis start out slowly, ...
Sonographic incidence of tendon microtears in athletes with chronic Achilles tendinosis
OBJECTIVE: To assess the number and distribution of tendon microtears in asymptomatic controls and athletes with chronic Achilles tendinitis or partial thickness tears using high resolution ultrasound. METHODS: The mean number of microtears in three random tendon cross sections were recorded per tendon third in 19 asymptomatic volunteers, 16 athletes with symptomatic chronic Achilles tendinitis, and eight athletes with partial
W. W. Gibbon; J. R. Cooper; G. S. Radcliffe
Extracorporeal shock wave therapy in chronic calcific tendonitis of the shoulder - Is it effective ?
Extracorporeal shock wave therapy has been claimed to be an effective non-invasive treatment for chronic calcific tendonitis of the supraspinatus tendon. However many trials have been criticised for not achieving necessary scientific standards. We report a prospective, single blinded, randomised control trial of 20 patients, which looked into effectiveness of the therapy. Subjectively, 45% of the treated patients were satisfied
Anthony H EARNDEN; Aravind D ESAI; Anand K ARMEGAM; Mark F LANNERY
Purpose The purpose of this study was to evaluate clinical and anatomic outcomes of patients following transtendon rotator-cuff repair of partial articular supraspinatus tendon avulsion (PASTA) lesions. Patients and methods Patients in the senior author�s practice who had isolated PASTA lesions treated by transtendon rotator-cuff repair were included (n=8) and retrospectively reviewed. All patients were evaluated preoperatively and at a mean of 21.2 months (�9.7 months) postoperatively using standardized clinical evaluation (physical exam, American Shoulder and Elbow Surgeons, and Simple Shoulder Test). All patients underwent postoperative imaging with a magnetic resonance imaging arthrogram. Results There was a significant improvement in American Shoulder and Elbow Surgeons (42.7�17.5 to 86.9�25.2) and Simple Shoulder Test (4.6�3.2 to 10.1�3.8) scores from pre- to postoperative, respectively. Postoperative imaging demonstrated full-thickness medial cuff tearing in seven patients, and one patient with a persistent partial articular surface defect. Conclusion Transtendon repair of PASTA lesions may lead to improvements in clinical outcome. However, postoperative imaging demonstrated a high incidence of full-thickness rotator-cuff defects following repair. PMID:25114604
Woods, Tom C; Carroll, Michael J; Nelson, Atiba A; More, Kristie D; Berdusco, Randa; Sohmer, Stephen; Boorman, Richard S; Lo, Ian KY
The partial articular surface tendon avulsion (PASTA) is a common lesion that involves the supraspinatus tendon in most cases. We present an arthroscopic fixation technique for a previously undescribed lesion that may be considered a variant of the PASTA. The lesion involves a partial avulsion of the greater tuberosity with an intact deep insertion of the supraspinatus tendon into the fractured bone fragment and an intact superficial insertion of the supraspinatus into the unavulsed lateral aspect of the greater tuberosity: a "bony PASTA" lesion. The surgical technique involves the use of a 70 degree arthroscope to provide an "end-on" view of the pathology. A superior-medial transmuscular portal is used for anchor insertion and suture management; the portal avoids damage to the intact tendinous insertion of the supraspinatus, which can occur during transtendon anchor/screw insertion. Abduction of the arm to 50 degrees, after creation of the portal and passage of the cannula, permits an optimal "deadman" angle of anchor placement. An angled suture grasper is used to retrieve the 4 suture strands from the double-loaded suture anchor through the intact superficial and deep supraspinatus tendon fibers along the length of the fracture; these are tied as 2 mattress sutures over the tendon fibers in the subacromial space by use of sliding-locking knots. Adequacy of reduction is confirmed by intra-articular arthroscopic observation during movement of the extremity through its complete range of motion. PMID:17637417
Bhatia, Deepak N; de Beer, Joe F; van Rooyen, Karin S
Skin Hypersensitivity to Sun Light Due to Doxycycline Ingestion Causing Hand Partial-Thickness Burn
Drugs hypersensitivity should be remembered when placing patients on any form of medications. In this case we present skin hypersensitivity to sun light due to doxycycline ingestion causing hand partial-thickness burn. PMID:24527377
Simman, Richard; Raynolds, David
Summary Background: the histological architecture of the insertion after a rotator cuff repair is completely different from that of normal tendon-bone insertions. Analysis of normal insertions by electron microscopy may enhance the understanding of the pathophysiology of tendon-to-bone healing after rotator cuff repair. The present study examined the normal supraspinatus insertion in rats using a new three-dimensional (3D) electron microscopic method, focused ion beam/scanning electron microscope (FIB/SEM) tomography. Methods: normal supraspinatus insertion of adult Sprague-Dawley rats was analyzed. FIB/SEM tomography was performed on the entire insertion. The obtained serial images were reconstructed, and the 3D cellular morphology and organization of collagen bundles was observed. Results: the cellular shapes between the tendon-cartilage interface were successfully reconstructed. The cells in the cartilage region were spherical without any cellular processes, while the cells in the intermediate region had some cellular processes oriented longitudinally along the collagen bundles. In addition, these 2 regions were smoothly transferred under ultrastructural resolution. Conclusions: structures at the normal insertion gradually changed from the fibrous cartilage to the tendon midsubstance, which may contribute to the biomechanical strength of the site. These novel cell characteristics may provide necessary knowledge for better regeneration of tendon-to-bone insertions after rotator cuff repair. PMID:25332933
Kanazawa, Tomonoshin; Gotoh, Masafumi; Ohta, Keisuke; Shiba, Naoto; Nakamura, Kei-ichiro
Summary We evaluated whether matrix metalloproteases and their inhibitors are involved in extracellular matrix remodelling and degradation of chronic rotator cuff tears. Tendon samples were harvested from 13 patients who underwent arthroscopic repair of a rotator cuff tear. Supraspinatus specimens were harvested en bloc from the arthroscopically intact middle portion of the tendon, more than 1 cm lateral to the torn edge, from the lateral edge of the tear, and from the superior margin of the macroscopically intact subscapularis tendon, used as control. The collagenases, the stromelysins, and the tissue inhibitors of metalloprotease arrays were analyzed blindly by multiplex sandwich ELISA in each specimen. Histological evidence of tendinopathy was present in all patients with a rotator cuff tear, but not in the macroscopically intact subscapularis tendon. There were significantly increased levels of MMP 1, MMP 2, MMP 3, TIMP-1, and TIMP-2 in all specimens examined, including the macroscopically intact portion of the supraspinatus tendon and the subscapularis (control specimens). The levels of specific matrix metalloproteases and their inhibitors are altered in torn rotator cuff tendons, but also in the macroscopically and histologically intact tendons. These changes extended medially to the site of tendon tear, and to other tendons. PMID:24367772
Castagna, Alessandro; Cesari, Eugenio; Garofalo, Raffaele; Gigante, Antonio; Conti, Marco; Markopoulos, Nikolaos; Maffulli, Nicola
... as a result of injury, overuse, or with aging as the tendon loses elasticity. Any action that places prolonged repetitive strain on the forearm muscles can cause tendonitis. The most common symptom of ...
Partial thickness burns (PTB) usually heal within 3 weeks. Prevention of infection and desiccation of the wounds are crucial for optimal healing. Early tangential excision of the burn eschar and allografting prevent deepening of the burns, and are therefore advocated for treatment with the best functional and aesthetic results. For superficial partial thickness burns (SPTB) conservative use of topical antimicrobial agents with frequent dressing changes are implemented. We compared the conservative treatment for PTBs and SPTBs to grafting cryopreserved cadaveric allografts with no prior excision. Twelve patients with flame PTB areas were allografted after mechanical debridement without excision of the burn wounds. The allografts were cadaveric skin cryopreserved by programmed freezing and stored at -180 degrees C for 30-48 months. Matching burns for depth and area were treated with silver sulfadiazine (SSD) one to two times daily until healing or debridement and grafting were required. It was found that 80 per cent of the cryopreserved allografts adhered well and 76 per cent of the treated areas healed within 21 days, whereas only 40 per cent of the SSD-treated burns healed within 21 days. Partial thickness burns can be treated successfully with viable human allografts (cryopreserved cadaveric skin) with no prior surgical excision. The burn wounds heal well within 3 weeks. For deep partial thickness burns (DPTB) treatment with allografts has no advantage if they have not been previously excised. PMID:9568334
Eldad, A; Din, A; Weinberg, A; Neuman, A; Lipton, H; Ben-Bassat, H; Chaouat, M; Wexler, M R
Gingival fenestration is a rare pathological entity, scarcely described in the literature. The present paper has reported a case of a 22-year-old male patient with a �Gingival fenestration� in the lower left central incisor. The lesion was successfully treated using a coronally positioned partial thickness graft under 4 X magnification, with excellent aesthetic results. PMID:24392432
Patel, Punit Vaibhav; Kumar, Naresh; Durrani, Farhan
The clinically important tendons around the elbow include the biceps and triceps brachii and the flexor and extensor muscles of the forearm. Familiarity with the normal magnetic resonance (MR) appearance of these structures facilitates the MR diagnosis of tendon abnormalities. Often referred to as epicondylitis, degeneration of the flexor or extensor groups is a common clinical complaint, treated conservatively and usually not requiring MR imaging. Imaging may play a role in unusual or severe cases; elevated signal in the appropriate common tendon origin is typically seen on T2 weighted images. Significant injury or disruption of the distal biceps or triceps tendons is a rare event, usually related to an acute event. Discontinuity of these tendons is best imaged using sagittal and axial T2 weighted sequences. Partial tears may demonstrate tendon irregularity and elevated signal within and around the tendon. PMID:11387099
Sonin, Andrew
Bifurcated intraarticular long head of biceps tendon
Though rare, many anomalous origins of long head of the biceps tendon (LHBT) have been reported in the literature. Anatomic variations commonly explained are a third humeral head, anomalous insertion, congenital absence and adherence to the rotator cuff. We report a rare case who underwent shoulder arthroscopy with impingement symptoms where in LHBT was found to be bifurcated with a part attached to superior labrum and the other part to the posterior capsule of joint. Furthermore, intraarticular portion of LHBT was adherent to the undersurface of the supraspinatus tendon. Awareness of such an anatomical aberration during the shoulder arthroscopy is of great importance as it can potentially avoid unnecessary confusion and surgery. PMID:25143652
Pandey, Vivek; van Laarhoven, Simon Nurettin; Arora, Gaurav; Rao, Sripathi
Optimal treatment of partial thickness burns in children: a systematic review.
A large part of the patient population of a burn centre consists of children, most of whom are younger than four years. The majority of these young children suffer from superficial and deep partial thickness scald burns that may easily deepen to full thickness burns. A proper wound therapy, that prevents infection and ensures a moist wound condition, might prevent the deterioration of the wound. Therefore, we performed a systematic review of wound management and dressing materials to select the best treatment option for children with burns. A search in Medline and Embase revealed 51 articles for a critical appraisal. The articles were divided into randomized controlled trials, cohort studies and a group of case-reports. Total appraisal did not differ much amongst the groups; the level of evidence was highest in the randomized controlled trials and lowest in the case-reports. In 16 out of 34 comparative studies, silver sulfadiazine or a silver sulfadiazine/chlorhexidine-gluconate combination was the standard of wound care treatment. The competitor dressing was Biobrane(�) in six studies and amnion membrane in three. Tulle gauze, or tulle gauze impregnated with an antibacterial addition were the standard of care treatment in seven studies. In general, membranous dressings like Biobrane(�) and amnion membrane performed better than the standard of care on epithelialization rate, length of hospital stay and pain for treatment of partial thickness burns in children. However, hardly any of the studies investigated long-term results like scar formation. PMID:24290852
Vloemans, A F P M; Hermans, M H E; van der Wal, M B A; Liebregts, J; Middelkoop, E
Background: Acticoat?(Smith & Nephew, Hull, UK) is a silver-coated dressing reported to reduce infection and exhibit antimicrobial activity in wounds. Objective: The purpose of the present study was to compare the efficacy of acticoatand 1% silver sulfadiazine (1% AgSD) for treatment of partial thickness burn wounds. Material and Method: The authors reviewed 50 patients who had partial thickness burn wounds
Pornprom Muangman
Effects of isotretinoin treatment on cartilage and tendon thicknesses: an ultrasonographic study.
Effects of retinoic acid on collagen synthesis and cartilage have previously been shown. However, its effects on cartilage and tendons in humans have not been studied yet. Therefore, in order to provide a morphologic insight, the aim of this study was to measure femoral cartilage, Achilles and supraspinatus tendon thicknesses in patients under systemic isotretinoin treatment by using ultrasound. Fifteen patients (nine F, six M) who used isotretinoin for their acnes were included. All patients were treated with isotretinoin 0.5�mg/kg/day for the first month, and the dosage was escalated up to 1�mg/kg/day thereafter. Distal femoral cartilage, supraspinatus, and Achilles tendons thicknesses have been evaluated both before the treatment and at the end of the third month. Femoral cartilage thicknesses were assessed from three midpoints bilaterally; medial condyle, lateral condyle, and intercondylar area. Short/long-axis diameters and cross-sectional area of the Achilles tendons and axial tendon thicknesses of supraspinatus tendon were evaluated from the nondominant side. The mean age of the patients was 20.1?�?4.9�years, and body mass index was 21.7?�?2.5�kg/m(2). Although posttreatment cartilage measurements of 30 knees were lower for the three midpoints, it reached significance only for lateral condyle (p?=?0.05). In addition, posttreatment tendon measurements were not statistically significant compared with pretreatment values (all p?>?0.05). Systemic isotretinoin treatment seems to make cartilage thinner. Further studies considering histological and molecular evaluations with more sample sizes are awaited. PMID:24985041
Y?ld?zg�ren, Mustafa Turgut; Karata? To?ral, Arzu; Baki, Ali Erdem; Ekiz, Timur
Supraspinatus and infraspinatus compartment syndrome following scapular fracture
Acute compartment syndrome occurs when pressure within a confined fascial space rises to a level impairing microvascular perfusion to surrounding tissues.[1234567] The majority of the reported literature is based on lower extremity compartment syndrome, but any muscle group within an osteofascial compartment has the potential to develop compartment syndrome. We report a case of a 64-year-old male who developed an acute compartment syndrome of both the supraspinatus and infraspinatus after sustaining a severely comminuted scapula fracture. Diagnosis of compartment syndrome was made after intracompartmental pressure measurements of the supraspinatus and infraspinatus revealed pressures within 30 mmHg of the diastolic blood pressure, prompting emergency decompressive fasciotomy. At final follow-up, the examination revealed full shoulder strength with near-full range of motion. There were no signs of sequelae from compartment syndrome at any point. Few case reports describe compartment syndrome of the periscapular fascial compartments. However, these cases were either retrospectively diagnosed[89] or diagnosed via magnetic resonance imaging (MRI) findings and lab values.[910] Surgical management of acute compartment syndrome of the supraspinatus has been reported in only one other case.[10] To our knowledge, we report the only case of a patient with acute compartment syndrome of both the supraspinatus and infraspinatus compartments treated with emergent decompressive fasciotomy. Due to the devastating complications and functional loss of a missed diagnosis of compartment syndrome, a high index of clinical suspicion for developing compartment syndrome must be maintained in every fracture setting, regardless of anatomic location or rarity of reported cases. PMID:23858293
Kenny, Ryan M.; Beiser, Christopher W.; Patel, Arun
ERK2 dependent signaling contributes to wound healing after a partial-thickness burn
Burn healing is a complex physiological process involving multiple cell activities, such as cell proliferation, migration and differentiation. Although extracellular signal-regulated kinases (ERK) have a pivotal role in regulating a variety of cellular responses, little is known about the individual functions of ERK isoform for healing in vivo. This study investigated the role of ERK2 in burn healing. To assess this, Erk2{sup +/-} mice generated by gene targeting were used. The resultant mice exhibited significant delay in re-epithelization of partial-thickness burns in the skin in comparison to wild-type. An in vitro proliferation assay revealed that keratinocytes from Erk2{sup +/-} mice grew significantly slower than those prepared from wild-type. These results highlight the importance of ERK2 in the process of burn healing.
Satoh, Yasushi [Department of Biochemistry, National Defense Medical College, 3-2 Namiki, Tokorozawa 359-8513 (Japan)], E-mail: firstname.lastname@example.com; Saitoh, Daizoh [Division of Traumatology, Research Institute, National Defense Medical College, 3-2 Namiki, Tokorozawa 359-8513 (Japan); Takeuchi, Atsuya; Ojima, Kenichiro; Kouzu, Keita; Kawakami, Saki [Department of Biochemistry, National Defense Medical College, 3-2 Namiki, Tokorozawa 359-8513 (Japan); Ito, Masataka [Department of Developmental Anatomy and Regenerative Biology, National Defense Medical College, 3-2 Namiki, Tokorozawa 359-8513 (Japan); Ishihara, Masayuki [Division of Biomedical Engineering, Research Institute, National Defense Medical College, 3-2 Namiki, Tokorozawa 359-8513 (Japan); Sato, Shunichi [Division of Biomedical Information Science, Research Institute, National Defense Medical College, 3-2 Namiki, Tokorozawa 359-8513 (Japan); Takishima, Kunio [Department of Biochemistry, National Defense Medical College, 3-2 Namiki, Tokorozawa 359-8513 (Japan)
Mineral Distributions at the Developing Tendon Enthesis
Tendon attaches to bone across a functionally graded interface, �the enthesis�. A gradient of mineral content is believed to play an important role for dissipation of stress concentrations at mature fibrocartilaginous interfaces. Surgical repair of injured tendon to bone often fails, suggesting that the enthesis does not regenerate in a healing setting. Understanding the development and the micro/nano-meter structure of this unique interface may provide novel insights for the improvement of repair strategies. This study monitored the development of transitional tissue at the murine supraspinatus tendon enthesis, which begins postnatally and is completed by postnatal day 28. The micrometer-scale distribution of mineral across the developing enthesis was studied by X-ray micro-computed tomography and Raman microprobe spectroscopy. Analyzed regions were identified and further studied by histomorphometry. The nanometer-scale distribution of mineral and collagen fibrils at the developing interface was studied using transmission electron microscopy (TEM). A zone (?20 �m) exhibiting a gradient in mineral relative to collagen was detected at the leading edge of the hard-soft tissue interface as early as postnatal day 7. Nanocharacterization by TEM suggested that this mineral gradient arose from intrinsic surface roughness on the scale of tens of nanometers at the mineralized front. Microcomputed tomography measurements indicated increases in bone mineral density with time. Raman spectroscopy measurements revealed that the mineral-to-collagen ratio on the mineralized side of the interface was constant throughout postnatal development. An increase in the carbonate concentration of the apatite mineral phase over time suggested possible matrix remodeling during postnatal development. Comparison of Raman-based observations of localized mineral content with histomorphological features indicated that development of the graded mineralized interface is linked to endochondral bone formation near the tendon insertion. These conserved and time-varying aspects of interface composition may have important implications for the growth and mechanical stability of the tendon-to-bone attachment throughout development. PMID:23152788
Schwartz, Andrea G.; Pasteris, Jill D.; Genin, Guy M.; Daulton, Tyrone L.; Thomopoulos, Stavros
Lanolin and epidermal growth factor in healing of partial-thickness pig wounds.
A total of 80 partial-thickness wounds (4.4 cm2 size, 400 micron deep) was inflicted by electrokeratome in the dermal skin layer of four piglets, 15 kg body weight. The wounds were treated with gauze (control), lanolin cream (Lanolor or Lanolin with emulsifiers, Squibb) or with human epidermal growth factor (EGF) delivered in lanolin cream (10 micrograms EGF/mL cream). The treatment was applied every 12 hours for 12 to 120 hours after wounding. The reepithelization rate of the wound was determined by standardized morphometric method. In addition, we measured the thickness of the dermis and cell counts in the dermis. We found that most of the statistically significant enhancement of the epithelization rate, thickness of the dermis, and higher cell count in the dermis were attributed to the effect of lanolin cream alone. The additional significant enhancement of healing by EGF over that of lanolin alone was documented in one of our experiments, but was only marginal. In another experiment using another commercial formulation of lanolin, we found no difference between the effect of EGF and lanolin. Several hypotheses were suggested to explain the effect of the two tested lanolin cream formulations, which induced strong inflammatory reaction in the wound. PMID:3262107
Chvapil, M; Gaines, J A; Gilman, T
The Use of EZ Derm� in Partial-Thickness Burns: An Institutional Review of 157 Patients
Objectives: To evaluate the use of EZ Derm� (Molnlycke Health Care, US, LLC, Norcross, GA) on partial-thickness burns. Methods: A retrospective review of medical records from patients presenting to the Tampa General Regional Burn Center from January 1, 2008, through January 1, 2012, was conducted. A hospitalwide list of patients was generated on the basis of the presence of charge codes for EZ Derm�. All encounters that did not pass through the Burn Unit were excluded. Applicable charts were reviewed for basic patient characteristics, burn characteristics, outcomes, and complications. Complications were defined as premature separation of EZ Derm�, deviation from a flat fully epithelized wound at the time of final EZ Derm� separation and hypertrophic/keloid scaring. Results: A total of 157 patients were identified and met the study criteria. Eighteen complications were reported from 16 of the 157 patients. Complications were attributed to positioning (2/133 = 1.5%), infection (4/133 = 3.0%), incomplete epithelialization at time of separation (3/133 = 2.2%), need for additional excision and grafting (6/133 = 4.5%), hypertrophic scaring (2/60 = 3.3), and cryptogenic (1/133 = 0.75). Conclusions: EZ Derm� has proven to be a robust wound dressing that provides cost-effective, consistent durable wound coverage with minimal complications that resolve without long-term sequela. PMID:23573334
Troy, Jared; Karlnoski, Rachel; Downes, Katheryne; Brown, Kimberly S.; Cruse, C. Wayne; Smith, David J.; Payne, Wyatt G.
Extracorporeal shock wave therapy (ESWT) enhances tissue vascularization and neoangiogenesis. Recent animal studies showed improved soft tissue regeneration using ESWT. In most cases, deep partial-thickness burns require skin grafting; the outcome is often unsatisfactory in function and aesthetic appearance. The aim of this study was to demonstrate the effect of ESWT on skin regeneration after deep partial-thickness burns. Under general anesthesia, two standardized deep partial-thickness burns were induced on the back of 30 male Wistar rats. Immediately after the burn, ESWT was given to rats of group 1 (N = 15), but not to group 2 (N = 15). On days 5, 10, and 15, five rats of each group were analyzed. Reepithelialization rate was defined, perfusion units were measured, and histological analysis was performed. Digital photography was used for visual documentation. A wound score system was used. ESWT enhanced the percentage of wound closure in group 1 as compared to group 2 (P < 0.05). The reepithelialization rate was improved significantly on day 15 (P < 0.05). The wound score showed a significant increase in the ESWT group. ESWT improves skin regeneration of deep partial-thickness burns in rats. It may be a suitable and cost effective treatment alternative in this type of burn wounds in the future. PMID:25431664
Djedovic, Gabriel; Kamelger, Florian Stefan; Jeschke, Johannes; Piza-Katzer, Hildegunde
Extracorporeal shock wave therapy (ESWT) enhances tissue vascularization and neoangiogenesis. Recent animal studies showed improved soft tissue regeneration using ESWT. In most cases, deep partial-thickness burns require skin grafting; the outcome is often unsatisfactory in function and aesthetic appearance. The aim of this study was to demonstrate the effect of ESWT on skin regeneration after deep partial-thickness burns. Under general anesthesia, two standardized deep partial-thickness burns were induced on the back of 30 male Wistar rats. Immediately after the burn, ESWT was given to rats of group 1 (N = 15), but not to group 2 (N = 15). On days 5, 10, and 15, five rats of each group were analyzed. Reepithelialization rate was defined, perfusion units were measured, and histological analysis was performed. Digital photography was used for visual documentation. A wound score system was used. ESWT enhanced the percentage of wound closure in group 1 as compared to group 2 (P < 0.05). The reepithelialization rate was improved significantly on day 15 (P < 0.05). The wound score showed a significant increase in the ESWT group. ESWT improves skin regeneration of deep partial-thickness burns in rats. It may be a suitable and cost effective treatment alternative in this type of burn wounds in the future. PMID:25431664
Kamelger, Florian Stefan; Jeschke, Johannes; Piza-Katzer, Hildegunde
Percutaneous Achilles Tendon Lengthening
... percutaneous Achilles tendon lengthening, specific complications are rare. Wound problems such as nonhealing incisions or infection can occur. The Achilles tendon can remain tight after surgery. The Achilles tendon can also completely rupture during ...
Arthroscopic biceps tendon tenodesis: the anchorage technical note.
Treatment of long head biceps (LHB) tendon pathology has become an area of renewed interest and debate among orthopaedic surgeons in recent years. The background of this manuscript is a description of biceps tenodesis which ensure continual dynamic action of the tendon which depresses the head and impedes lateral translation. A new technique has been developed in order to treat LHB tendon irreversible structural abnormalities associated with cuff rotator lesions. This technique entails the construction of a biological anchor between the LHB and supraspinatus and/or infraspinatus tendons according to arthroscopic findings. The rationale, although not supported by biomechanical studies is to obtain a triple, biomechanical effect. The first of these biomechanical effects which we try to promote through the procedure of transposition is the elimination of the deviation and oblique angle which occurs as the LHB completes its intra-articular course prior to reaching the bicipital groove. Furthermore, we have found this technique extremely useful in the presence of large ruptures of the rotator cuff with muscle retraction. The most common complication associated to this particular method, observed in less than 3%, is failed biological fixation which manifests as subsidence of the tenodesis and consequent descent of the tendon with evident aesthetic deformity. PMID:16374589
Castagna, A; Conti, M; Mouhsine, E; Bungaro, P; Garofalo, R
ATP hydrolysis reduces neutrophil infiltration and necrosis in partial-thickness scald burns in mice
Objective Extracellular ATP, present in thermally-injured tissue, modulates the inflammatory response and causes significant tissue damage. We hypothesize that neutrophil infiltration and ensuing tissue necrosis would be mitigated by removing ATP-dependent signaling at the burn site. Methods Mice were subjected to 30% total-body- surface-area partial-thickness scald burn by dorsal skin immersion in a water bath at 60�C or 20�C (non-burn controls). In the treatment arm, an ATP hydrolyzing enzyme, apyrase, was applied directly to the site immediately after injury. Skin was harvested after 24 hours and 5 days for hematoxylin and eosin stain (H&E), elastase, and Ki-67 staining. TNF-? and IFN-? expression were measured through qRT-PCR. Results At 24 hours, the amount of neutrophil infiltration was different between the burn and burn + apyrase groups (p<0.001). Necrosis was less extensive in the apyrase group when compared to the burn group at 24 hours and 5 days. TNF-? and IFN-? expression at 24 hours in the apyrase group was lower than in the burn group (p <0.05). However, Ki-67 signaling was not significantly different among the groups. Conclusions Our results support the role of extracellular ATP in neutrophil activity. We demonstrate that ATP hydrolysis at the burn site allays the neutrophil response to thermal injury and reduces tissue necrosis. This decrease in inflammation and tissue necrosis is at least partially due to TNF-? and IFN-? signaling. Apyrase could be used as topical inflammatory regulators to quell the injury caused by inflammation. PMID:23877144
Bayliss, Jill; DeLaRosa, Sara; Wu, Jianfeng; Peterson, Jonathan R; Eboda, Oluwatobi N.; Su, Grace L; Hemmila, Mark; Krebsbach, Paul H.; Cederna, Paul S.; Wang, Stewart C; Xi, Chuanwu; Levi, Benjamin
Extracellular adenosine triphosphate (ATP), present in thermally injured tissue, modulates the inflammatory response and causes significant tissue damage. The authors hypothesize that neutrophil infiltration and ensuing tissue necrosis would be mitigated by removing ATP-dependent signaling at the burn site. Mice were subjected to 30% TBSA partial-thickness scald burn by dorsal skin immersion in a water bath at 60 or 20�C (nonburn controls). In the treatment arm, an ATP hydrolyzing enzyme, apyrase, was applied directly to the site immediately after injury. Skin was harvested after 24 hours and 5 days for hematoxylin and eosin stain, elastase, and Ki-67 staining. Tumor necrosis factor (TNF)-? and interferon (IFN)-? expression were measured through quantitative real-time polymerase chain reaction. At 24 hours, the amount of neutrophil infiltration was different between the burn and burn + apyrase groups (P < .001). Necrosis was less extensive in the apyrase group when compared with the burn group at 24 hours and 5 days. TNF-? and IFN-? expression at 24 hours in the apyrase group was lower than in the burn group (P < .05). However, Ki-67 signaling was not significantly different among the groups. The results of this study support the role of extracellular ATP in neutrophil activity. The authors demonstrate that ATP hydrolysis at the burn site allays the neutrophil response to thermal injury and reduces tissue necrosis. This decrease in inflammation and tissue necrosis is at least partially because of TNF-? and IFN-? signaling. Apyrase could be used as topical inflammatory regulators to quell the injury caused by inflammation. PMID:23877144
Bayliss, Jill; Delarosa, Sara; Wu, Jianfeng; Peterson, Jonathan R; Eboda, Oluwatobi N; Su, Grace L; Hemmila, Mark; Krebsbach, Paul H; Cederna, Paul S; Wang, Stewart C; Xi, Chuanwu; Levi, Benjamin
Role of endogenous TRPV1 agonists in a postburn pain model of partial-thickness injury.
Oxidized linoleic acid metabolites (OLAMs) are a class of endogenous transient receptor potential vanilloid 1 (TRPV1) channel agonists released on exposure of tissue to transient noxious temperatures. These lipid compounds also contribute to inflammatory and heat allodynia. Because persistent pain after a burn injury represents a significant clinical challenge for treatment, we developed an in vivo rat model of partial-thickness cutaneous thermal injury and examined whether TRPV1 and specific OLAM metabolites play a role in mediating postburn pain injury. This peripheral model of burn injury had marked thermal allodynia peaking at 24h after thermal injury, with allodynia being maintained for up to 7d. Immunohistochemical characterization of tissue taken from injury sites revealed an increase in leukocyte/macrophage infiltration that was colocalized with TRPV1-positive fibers. Using this peripheral thermal injury model, we found that pharmacological blockade of peripheral TRPV1 receptors reduced thermal allodynia by about 98%. Moreover, there was a significant increase in OLAM levels compared to naive controls in hind paw skin biopsies. Additional studies of the metabolism of [C(14)]-linoleic acid in skin biopsies revealed the role of the cytochrome P450 (CYP) system in mediating the metabolism of linoleic acid after thermal injury. Finally, we demonstrated that direct inhibition of OLAMs using OLAM antibodies and indirect inhibition using the CYP inhibitor ketoconazole significantly reduced postburn thermal allodynia. Collectively, these findings point to a novel role of the OLAMs and CYP-related enzymes in generating postburn allodynia via activation of peripheral TRPV1. PMID:23891895
Green, Dustin P; Ruparel, Shivani; Roman, Linda; Henry, Michael A; Hargreaves, Kenneth M
Introduction Vitreomacular traction syndrome has recently been recognized as a distinct clinical condition. It may lead to many complications, such as cystoid macular edema, macular pucker formation, tractional macular detachment, and full-thickness macular hole formation. Case presentation We report a case of vitreomacular traction syndrome with eccentric traction at the macula and a partial-thickness macular hole in a 63-year-old Pakistani Punjabi man. The patient was evaluated using optical coherence tomography, and he underwent a successful pars plana vitrectomy. After the operation, his foveal contour regained normal configuration, and his visual acuity improved from 20/60 to 20/30. Conclusions Pars plana vitrectomy prevents the progression of a partial thickness macular hole in vitreomacular traction syndrome. The relief of traction by vitrectomy restores foveal anatomy and visual acuity in this condition. PMID:20205799
The standard treatment of partial-thickness burns includes topical silver products such as silver sulfadiazine (SSD) cream and enclosed dressings including silver-impregnated foam (Mepilex Ag; Molnlycke Health Care, Gothenburg, Sweden) and silver-laden sheets (Aquacel Ag; ConvaTec, Skillman, NJ). The current state of health care is limited by resources, with an emphasis on evidence-based outcomes and cost-effective treatments. This study includes a decision analysis with an incremental cost-utility ratio comparing enclosed silver dressings with SSD in partial-thickness burn patients with TBSA less than 20%. A comprehensive literature review was conducted to identify clinically relevant health states in partial-thickness burn patients. These health states include successful healing, infection, and noninfected delayed healing requiring either surgery or conservative management. The probabilities of these health states were combined with Medicare CPT reimbursement codes (cost) and patient-derived utilities to fit into the decision model. Utilities were obtained using a visual analog scale during patient interviews. Expected cost and quality-adjusted life years (QALYs) were calculated using the roll-back method. The incremental cost-utility ratio for enclosed silver dressing relative to SSD was $40,167.99/QALY. One-way sensitivity analysis of complication rates confirmed robustness of the model. Assuming a maximum willingness to pay $50,000/QALY, the complication rate for SSD must be 22% or higher for enclosed silver dressing to be cost effective. By varying complication rates for SSD and enclosed silver dressings, the two-way sensitivity analysis demonstrated the cost effectiveness of using enclosed silver dressing at the majority of complication rates for both treatment modalities. Enclosed silver dressings are a cost-effective means of treating partial thickness burns. PMID:24121806
Sheckter, Clifford C; Van Vliet, Michael M; Krishnan, Naveen M; Garner, Warren L
The objective of this study was to analyze which materials and methods are used for the management of partial and full thickness burns, as well as donor sites. An Internet survey was used to poll directors of burn centers around the world on their preferences for local treatment of different types of burns and donor sites. Results were tabulated and expressed as a percentage of the total number of answers for a given indication. Although many new wound care materials have been launched in the last decade, few of these actually are used widely. The most commonly used materials for partial thickness burns and donor sites are still silver sulphadiazine 1% cream, other antimicrobial ointments and creams and impregnated gauze type dressings. Of the newly available treatment modalities, only two silver dressings were chosen frequently as a primary option for the management of partial thickness burns and donor sites. For full thickness burns, the primary choice is excision and grafting. The diversity of dressings and techniques indicated as preferred in this survey, including many that are known to have side effects, indicates that there is no consensus on topical treatment of partial thickness burns and donor sites. Many respondents prefer "tried and true" materials over newer dressings, particularly if the latter have not been tested in a clinical trial. PMID:17925651
Hermans, Michel H E
There is increasing evidence for a progressive extracellular matrix change in rotator cuff disease progression. Directly surrounding the cell is the pericellular matrix, where assembly of matrix aggregates typically occurs making it critical in the response of tendon cells to pathological conditions. Studies in animal models have identified type VI collagen, fibrillin-1 and elastin to be located in the pericellular matrix of tendon and contribute in maintaining the structural and biomechanical integrity of tendon. However, there have been no reports on the localization of these proteins in human tendon biopsies. This study aimed to characterize the distribution of these ECM components in human rotator cuffs and gain greater insight into the relationship of pathology to tear size by analyzing the distribution and expression profiles of these ECM components. Confocal microscopy confirmed the localization of these structural molecules in the pericellular matrix of the human rotator cuff. Tendon degeneration led to an increased visibility of these components with a significant disorganization in the distribution of type VI collagen. At the genetic level, an increase in tear size was linked to an increased transcription of type VI collagen and fibrillin-1 with no significant alteration in the elastin levels. This is the first study to confirm the localization of type VI collagen, elastin and fibrillin-1 in the pericellular region of human supraspinatus tendon and assesses the effect of tendon degeneration on these structures, thus providing a useful insight into the composition of human rotator cuff tears which can be instrumental in predicting disease prognosis. PMID:25166893
Thakkar, Dipti; Grant, Tyler M; Hakimi, Osnat; Carr, Andrew J
Lateral Patellofemoral Ligament Reconstruction Using a�Quadriceps Tendon Graft
Medial patellar subluxation (MPS) is normally described after a lateral retinacular release. However, isolated MPS in the absence of a previous lateral release does occur. This type of patellar instability is often overlooked, and a high index of suspicion is needed for appropriate diagnosis and treatment. This report describes a technique developed in response to episodes of isolated MPS. The technique uses a partial-thickness graft from the quadriceps tendon to reconstruct the lateral patellofemoral ligament and provide stability to the lateral side of the patella. PMID:25264506
Saper, Michael G.; Shneider, David A.
Influence of tendon tears on ultrasound echo intensity in response to loading.
Acoustoelastic (AE) ultrasound image analysis is a promising non-invasive approach that uses load-dependent echo intensity changes to characterize stiffness of tendinous tissue. The purpose of this study was to investigate whether AE can detect localized changes in tendon stiffness due to partial and full-thickness tendon tears. Ovine infraspinatus tendons with different levels of damage (Intact, 33%, 66% and full thickness cuts initiated on the articular and bursal sides) were cyclically loaded in a mechanical testing system while cine ultrasound images were recorded. The load-induced changes in echo intensity on the bursal and articular side of the tendon were determined. Consistent with AE theory, the undamaged tendons exhibited an increase in echo intensity with tendon loading, reflecting the strain-stiffening behavior of the tissue. In the intact condition, the articular region demonstrated a significantly greater increase in echo intensity during loading than the bursal region. Cuts initiated on the bursal side resulted in a progressive decrease in echo intensity of the adjacent tissue, likely reflecting the reduced load transmission through that region. However, image intensity information was less sensitive for identifying load transmission changes that result from partial thickness cuts initiated on the articular side. We conclude that AE approaches may be useful to quantitatively assess load-dependent changes in tendon stiffness, and that disruption of AE behavior may be indicative of substantial tendon damage. PMID:25468301
Frisch, Kayt E; Marcu, David; Baer, Geoffrey S; Thelen, Darryl G; Vanderby, Ray
Diseases of the tendons and tendon sheaths.
Contracted flexor tendon leading to flexural deformity is a common congenital defect in cattle. Arthrogryposis is a congenital syndrome of persistent joint contracture that occurs frequently in Europe as a consequence of Schmallenberg virus infection of the dam. Spastic paresis has a hereditary component, and affected cattle should not be used for breeding purposes. The most common tendon avulsion involves the deep digital flexor tendon. Tendon disruptions may be successfully managed by tenorrhaphy and external coaptation or by external coaptation alone. Medical management alone is unlikely to be effective for purulent tenosynovitis. PMID:24534664
Steiner, Adrian; Anderson, David E; Desrochers, Andr�
Achilles tendon: US examination
Real-time ultrasonography (US) using linear-array probes and a stand-off pad as a ''waterpath'' was performed to evaluate the Achilles tendon in 67 patients (including 24 athletes) believed to have acute or chronic traumatic or inflammatory pathologic conditions. Tendons in 23 patients appeared normal on US scans. The 44 abnormal tendons comprised five complete and four partial ruptures, seven instances of postoperative change, and 28 cases of tendonitis. US depiction of the inner structure of the tendon resulted in the diagnosis of focal abnormalities, including partial ruptures, nodules, and calcifications. Tendonitis was characterized by enlargement and decreased echogenicity of the tendon. The normal US appearance of the Achilles tendon is described.
Fornage, B.D.
Achilles tendon rupture - aftercare
The Achilles tendon connects your calf muscles to your heel bone. Together, they help you push your heel off the ... your toes. You use these muscles and your Achilles tendon when you walk, run, and jump. If your ...
Many alternative therapies are used as first aid treatment for burns, despite limited evidence supporting their use. In this study, Aloe vera, saliva and a tea tree oil impregnated dressing (Burnaid) were applied as first aid to a porcine deep dermal contact burn, compared to a control of nothing. After burn creation, the treatments were applied for 20 min and the wounds observed at weekly dressing changes for 6 weeks. Results showed that the alternative treatments did significantly decrease subdermal temperature within the skin during the treatment period. However, they did not decrease the microflora or improve re-epithelialisation, scar strength, scar depth or cosmetic appearance of the scar and cannot be recommended for the first aid treatment of partial thickness burns. PMID:18603378
Cuttle, Leila; Kempf, Margit; Kravchuk, Olena; George, Narelle; Liu, Pei-Yun; Chang, Hong-En; Mill, Julie; Wang, Xue-Qing; Kimble, Roy M
Tendon structure, disease, and imaging
Summary Tendon imaging plays a critical role in evaluating tendon diseases and injuries including mechanical, degenerative, and overuse disease, inflammatory enthesitis, as well as partial and full thickness tears. Ultrasound and magnetic resonance imaging (MRI), each with unique benefits and limitations, are commonly utilized to assist in diagnosing these diseases and conditions. This review delineates important structural properties of tendon and biochemical changes occurring in tendon pathology. This review also examines commonly injured tendons including tendons of the elbow, tendons of the rotator cuff of the shoulder, hip abductor tendons, patellar tendons, and the Achilles tendon to help clinicians better recognize tendon disease. Finally, this paper introduces several emerging imaging techniques including T2 mapping, ultra-short echo time MRI, and sonoelastography as ways in which tendon imaging and evaluation may be improved. PMID:24932450
Weinreb, Jeffrey H.; Sheth, Chirag; Apostolakos, John; McCarthy, Mary-Beth; Barden, Benjamin; Cote, Mark P.; Mazzocca, Augustus D.
Distal biceps tendon ruptures continue to be an important injury seen and treated by upper extremity surgeons. Since the mid-1980s, the emphasis has been placed on techniques that limit complications or improve initial tendon-to-bone fixation strength. Recently, basic science research has expanded the knowledge base regarding the biceps tendon structure, footprint anatomy, and biomechanics. Clinical data have further delineated the results of conservative and surgical management of both partial and complete tears in acute or chronic states. The current literature on the distal biceps tendon is described in detail. PMID:23474326
Schmidt, Christopher C; Jarrett, Claudius D; Brown, Brandon T
Etiology and pathophysiology of tendon ruptures in sports.
Of all spontaneous tendon ruptures, complete Achilles tendon tears are most closely associated with sports activities (1-3). Sch�nbauer (3) reported that 75% of all ruptures of the Achilles tendon are related to sports. In Plecko & Passl (2) the number was 60%. In our material of 430 cases, the number of sports-related Achilles ruptures was very similar (62%), while only 2% of ruptures of other tendons were sports-related (P < 0.001) (1). Also, the majority of Achilles reruptures occurred in sports. The ruptures occurred most often in soccer (34%), track and field (16%) and basketball (14%). The distribution of Achilles ruptures according to different sports varies considerably from country to country, according to the national sport traditions. For example, in northern and middle Europe, soccer, tennis, track and field, indoor ball games, downhill skiing, and gymnastics are the most common; and in North America, football, basketball, baseball, tennis and downhill skiing dominate the statistics (1, 2, 4). In sports, some Achilles ruptures are not spontaneous or degeneration-induced but may occur as a consequence of the remarkably high forces that are involved in the performance (2). Ruptures in the high jump or triple jump are good examples. In such cases, failure in the neuromuscular protective mechanisms due to fatigue or disturbed co-ordination can frequently be found. The spontaneous complete rupture of the supraspinatus tendon of the rotator cuff does not occur very frequently in sports. Those sports that include high-energy throwing movements, such as American and Finnish baseball, American football, rugby and discuss and javelin throwing, may, however, produce this injury. Partial tears and inflammations of the rotator cuff complex are much more frequent in throwing sports. The complete rupture of the proximal long head of the biceps brachii tendon is rare among competitive and recreational athletes. In our material, under 2% of these ruptures were associated with sports activities (5). The rupture (avulsion) of the distal tendon of the biceps muscle is rare. In sports, gymnastics, body building and weight lifting have been said to be able to produce this injury (6). In general, complete ruptures of the quadriceps tendon and the patellar tendon occur most often in older individuals. In our study, the mean age of these patients was 65 years (5). However, these injuries do also occur in younger age groups, especially in athletes. In athletes, the rupture most frequently occurs in high-power sports events, such as high jump, basketball and weight lifting, at the age of 15-30 years. A chronic-patellar apicitis (jumper's knee) may predispose rupture of the tendon (7). As is the case with the rotator cuff complex, overuse inflammation and partial tears of the quadriceps and patellar tendons are one of the most characteristic athletic injuries. Complete spontaneous ruptures of other tendons in sports are rare, although the literature does provide case studies from almost every tendon the human body possesses (8-18). PMID:9211611
Kannus, P; Natri, A
Learning Fourier Descriptors for Computer-Aided Diagnosis of the Supraspinatus1
patients, separated into five pathology groups. The imaging protocol ensures that the supraspinatus is consistently oriented relative to the MR imaging 1 From the Medical Image Analysis Lab (O.v.K., G.H.) and Graphics, Usability, and Visualization (GrUVi) lab (O.v.K., H.Z.), School of Computing Science, Simon
Hamarneh, Ghassan
Partial thickness articular cartilage defects in the knee are commonly encountered clinical problems. Recently, use of radiofrequency-based devices for performing arthroscopic chondroplasty has gained popularity. However, published experimental studies using different methods for evaluating the histologic effects of radiofrequency-chondroplasty on surrounding cartilage offer contradictory results. To date, few clinical findings after radiofrequency-based chondroplasty have been reported. We present four patients where follow-up arthroscopy documented partial thickness articular defects treated previously with radiofrequency-based chondroplasty to be completely filled with stable repair tissue. No attempt was made to stimulate cartilage regeneration (ie, abrasion or microfracture) in any of these cases. PMID:15915832
Voloshin, Ilya; DeHaven, Kenneth E; Steadman, J Richard
... that arm. But sometimes an injury or small tear in the tendon can cause problems right away. Some of the ... do surgery to repair badly injured proximal biceps tendons, it's usually for adults. Kids and teens ... can include the following: Rest your arm. Stop ...
Local treatment of burn injuries with conventional anti-infective preparations does not provide the moist environment that promotes fast wound healing. In a randomized controlled trial the effects of liposome polyvinyl-pyrrolidone-iodine (PVP-I) hydrogel, a novel formulation of PVP-I in a liposome hydrogel with high water-binding capacity, were investigated in 43 patients with partial-thickness burn wounds in an intraindividual comparison with a conventional silver-sulfadiazine cream. Treatment with liposome PVP-I hydrogel resulted in significantly faster complete healing of the burn wounds compared with silver-sulfadiazine cream (9.9 +/- 4.5 days versus 11.3 +/- 4.9; P < 0.015). The cosmetic result (smoothness, elasticity, appearance) was rated as excellent for 37.0% of study wounds with liposome PVP-I hydrogel compared with 13.0% of wounds treated with silver-sulfadiazine cream. Local tolerability was good; handling and change of dressing were rated as easy. Local treatment with liposome PVP-I hydrogel thus provides fast wound healing with a favorable cosmetic result. PMID:17901735
Homann, Heinz-Herbert; Rosbach, Oliver; Moll, Wiebke; Vogt, Peter Maria; Germann, Guenter; Hopp, Michael; Langer-Brauburger, Birgit; Reimer, Karen; Steinau, Hans-Ulrich
Mechanical properties of the human achilles tendon
Objective. To determine whether the human Achilles tendon has higher material properties than other tendons and to test for strain rate sensitivity of the tendon.Design. Mechanical testing of excised tendons.Background. While the human Achilles tendon appears to experience higher in vivo stresses than other tendons, it is not known how the Achilles tendon's material properties compare with the properties of
Tishya A. L Wren; Scott A Yerby; Gary S Beaupr�; Dennis R Carter
Tendon Gradient Mineralization for Tendon to Bone Interface Integration
Tendon-to-bone integration is a great challenge for tendon or ligament reconstruction regardless of use of autograft or allograft tendons. We mineralized the tendon, thus transforming the tendon-to-bone into a �bone-to-bone� interface for healing. Sixty dog flexor digitorum profundus (FDP) tendons were divided randomly into 5 groups: 1) normal FDP tendon, 2) CaP (Non-extraction and mineralization without fetuin), 3) CaPEXT (Extraction by Na2HPO4 and mineralization without fetuin), 4) CaPFetuin (Non-extraction and mineralization with fetuin), and 5) CaPEXTFetuin (Extraction and mineralization with fetuin). The calcium and phosphate content significantly increased in tendons treated with combination of extraction and fetuin compared to the other treatments. Histology also revealed a dense mineral deposition throughout the tendon outer layers and penetrated into the tendon to a depth of 200 ?m in a graded manner. Compressive moduli were significantly lower in the four mineralized groups compared with normal control group. No significant differences in maximum failure strength or stiffness were found in the suture pull-out test among all groups. Mineralization of tendon alters the interface from tendon to bone into mineralized tendon to bone, which may facilitate tendon-to-bone junction healing following tendon or ligament reconstruction. PMID:23939935
Qu, Jin; Thoreson, Andrew R.; Chen, Qingshan; An, Kai-Nan; Amadio, Peter C.; Zhao, Chunfeng
The authors performed a study to compare the short-term clinical outcome between three methods for failed conservative treatment of the supraspinatus muscle tendinitis, extracorporeal shock wave therapy (ESWT) and open or arthroscopical subacromial decompression.
M. Haake; M. Rautmann; T. Wirth
Tendon injuries are the second most common injuries of the hand and therefore an important topic in trauma and orthopedic patients. Most injuries are open injuries to the flexor or extensor tendons, but less frequent injuries, e.g., damage to the functional system tendon sheath and pulley or dull avulsions, also need to be considered. After clinical examination, ultrasound and magnetic resonance imaging have proved to be important diagnostic tools. Tendon injuries mostly require surgical repair, dull avulsions of the distal phalanges extensor tendon can receive conservative therapy. Injuries of the flexor tendon sheath or single pulley injuries are treated conservatively and multiple pulley injuries receive surgical repair. In the postoperative course of flexor tendon injuries, the principle of early passive movement is important to trigger an �intrinsic� tendon healing to guarantee a good outcome. Many substances were evaluated to see if they improved tendon healing; however, little evidence was found. Nevertheless, hyaluronic acid may improve intrinsic tendon healing. PMID:22720265
Sch�ffl, Volker; Heid, Andreas; K�pper, Thomas
Role of Endogenous TRPV1 Agonists in a Post-Burn Pain Model of Partial-Thickness Injury
Oxidized linoleic acid metabolites (OLAMs) are a class of endogenous transient receptor potential vanilloid 1 (TRPV1) channel agonists released upon exposure of tissue to transient noxious temperatures. These lipid compounds also contribute to inflammatory and heat allodynia. As persistent pain after a burn injury represents a significant clinical challenge for treatment, we developed an in vivo rat model of partial thickness cutaneous thermal injury and examined whether TRPV1 and specific OLAM metabolites play a role in mediating post-burn pain injury. This peripheral model of burn injury had marked thermal allodynia peaking at 24 hours post thermal injury, with allodynia being maintained for up to 7 days. Immunohistochemical characterization of tissue taken from injury site revealed an increase of leukocyte/macrophage infiltration that was co-localized with TRPV1-positive fibers. Utilizing this peripheral thermal injury model we found that pharmacological blockade of peripheral TRPV1 receptors reduced thermal allodynia by about 67%. Moreover, there was a significant increase in OLAM levels compared to na�ve controls in hindpaw skin biopsies. Additional studies on metabolism of [C14]-linoleic acid in skin biopsies revealed the role of the cytochrome P450 (CYP) system in mediating the metabolism of linoleic acid post thermal injury. Finally, we demonstrated direct inhibition of OLAMs using OLAM antibodies and indirect inhibition using the CYP inhibitor ketoconazole significantly reduced post-burn thermal allodynia. Collectively, these findings point to a novel role of the OLAMs and CYP-related enzymes in generating post-burn allodynia via activation of peripheral TRPV1. PMID:23891895
Green, Dustin; Ruparel, Shivani; Roman, Linda; Henry, Michael A.; Hargreaves, Kenneth M.
... outside ankle bone Ankle instability or weakness Early treatment of a subluxation is critical, since a tendon that continues to sublux (move out of position) is more likely to tear or rupture. Therefore, if you feel the characteristic ...
Supraspinatus muscle atrophy and fatty infiltration are two distinct muscle abnormalities which can be seen after a chronic massive tear or suprascapular neuropathy. Isolated supraspinatus muscle denervation due to suprascapular nerve injury after shoulder dislocation is extremely rare. We report on a patient who developed isolated supraspinatus muscle atrophy and fatty infiltration after traumatic anterior shoulder instability. Possible explanations and etiologies of this rare condition are discussed in this report. PMID:22058642
Alomar, Abdulaziz Z.; Powell, Tom; Burman, Mark L.
Supraspinatus muscle atrophy and fatty infiltration are two distinct muscle abnormalities which can be seen after a chronic massive tear or suprascapular neuropathy. Isolated supraspinatus muscle denervation due to suprascapular nerve injury after shoulder dislocation is extremely rare. We report on a patient who developed isolated supraspinatus muscle atrophy and fatty infiltration after traumatic anterior shoulder instability. Possible explanations and etiologies of this rare condition are discussed in this report. PMID:22058642
Alomar, Abdulaziz Z; Powell, Tom; Burman, Mark L
Reepithelialization of deep burns requires spontaneous or active removal or debridement of the necrotic eschar, as recently defined by the American Burn Association. Debrase is a bromelain-derived enzymatic preparation that has been shown to result in rapid and selective debridement of human and animal burns. The authors hypothesized that rapid debridement of deep dermal burns with Debrase would result in earlier reepithelialization of the remaining dermis in a porcine model. Eighty deep dermal contact burns measuring 10 by 20 mm were created on the back and flanks of anesthetized domestic pigs (25 kg) using a brass template preheated in boiling water (100 degrees C) that was applied to the skin for a period of 30 seconds. The template was applied using a spring-loaded device designed to control the amount of pressure applied to the skin by the template. Burns were randomized to a 4-hour topical application of Debrase (lyophilized dry enzyme dissolved and activated in a hydrating vehicle) (n = 40) or its hydrating vehicle (n = 40) followed by daily application of a petrolatum-based antibiotic ointment. Wounds were visually assessed and photographed daily. Four-millimeter full-thickness punch biopsies were obtained for histological analysis using hematoxylin and eosin staining by a board-certified dermatopathologist masked to burn therapy at 7, 11, 13, and 15 days after injury. The primary outcome was the percentage of the burns that were completely reepithelialized at each time point. Secondary outcomes were time to complete reepithelialization and the mean percentage of reepithelialization on microscopic analysis. A sample of 40 burns in each group had 80% power to detect a 20% difference in the percentage of completely reepithelialized burns (two tailed, P < .05). The percentage of completely reepithelialized burns was higher for Debrase than control burns at days 11 (40.9% vs 3.1%; P = .002), 13 (87.5% vs 50%; P = .007), and 15 (97.5% vs 77.5%, P = .018). The mean (SD) percentage reepithelialization of Debrase-treated burns at 7 days was higher than of control burns (47.6% [3.2] vs 0% [0]; P < .001). A larger number of cells in the epidermis and dermis of debrided burns stained positive for the proliferation antigen Ki-67. There was no evidence of any adverse events in the normal skin adjacent to the Debrase-treated burns. Rapid enzymatic debridement of deep partial-thickness burns with Debrase results in earlier reepithelialization and cellular proliferation in swine, when compared with carrier and topical antibiotic dressings alone. PMID:20661148
Singer, Adam J; Taira, Breena R; Anderson, Ryon; McClain, Steve A; Rosenberg, Lior
Autologous hamstring tendon used for revision of quadiceps tendon tears.
A paucity of literature exists on quadriceps tendon reruptures. Failed quadriceps tendon repair can cause significant morbidity and disability. Surgical management of quadriceps tendon rerupture can be challenging due to tissue degeneration, tendon retraction, muscle atrophy, and poor bone fixation. A lack of guidance in the literature exists on the appropriate surgical techniques for managing quadriceps tendon reruptures.This article describes the case of a male recreational athlete with a failed primary quadriceps tendon repair who presented 10 months after rerupture. Examination was significant for morbid obesity, assisted ambulation, and a significant defect at the superior pole of the patella on the affected side. Intraoperative findings were consistent with a 2.0- to 4.5-cm tendon defect across the extensor mechanism with complete retinaculi tears. The authors performed a novel surgical approach for revision of quadriceps tears using a bilateral hamstring autograft through a quadriceps tendon weave and a transosseous patellar repair. Tendon length was restored, and extensor mechanism tension was reapproximated. Postoperatively, the patient achieved a good outcome and had returned to full, painless, sport participation at 2-year follow-up.This surgical technique is suitable for revision quadriceps tendon repairs of large tendon gap defects, repairs desiring tendon-to-bone in-growth, and repairs requiring large-force transmission across the repair. PMID:23590798
McCormick, Frank; Nwachukwu, Benedict U; Kim, Jaehon; Martin, Scott D
Collagen based dressings for acute burn wound management have been extensively used in India, particularly in the city of Chennai. Due to the high levels of humidity in our city, closed dressings become infected and treatment with topical antimicrobials, like Silver Sulfadiazine cream, quickly become desiccated. Collagen membrane dressings were manufactured by the biomaterial laboratory of the Central Leather Research Institute (CLRI), Government of India in Chennai, and then the process was patented. Collagen was extracted from bovine skin and Achilles tendons, and then reconstituted. This was used on burn wounds as dressings after clearance from the Institutional Review Board and Ethics Committees of the Hospital and CLRI. Continued research in this field to enable resulted in the design of silver sulphadiazine loaded alginate microspheres which were embedded in the reconstituted collagen. Controlled delivery of silver sulphadiazine. This collagen membrane was used in chronic infected burns. Low molecular weight heparin was given subcutaneously to improve wound healing in burn injuries and collagen membrane dressings were also applied. After several trials the process technology was patented. The advantages and disadvantages of the collagen membrane cover is elaborated in a group of 487 pediatric burn patients. The trial was conducted at the burn unit of Kanchi Kamakoti Childs Trust Hospital (KKCTH) in Chennai, India. PMID:24133405
Mathangi Ramakrishnan, K; Babu, M; Mathivanan; Jayaraman, V; Shankar, J
Summary Collagen based dressings for acute burn wound management have been extensively used in India, particularly in the city of Chennai. Due to the high levels of humidity in our city, closed dressings become infected and treatment with topical antimicrobials, like Silver Sulfadiazine cream, quickly become desiccated. Collagen membrane dressings were manufactured by the biomaterial laboratory of the Central Leather Research Institute (CLRI), Government of India in Chennai, and then the process was patented. Collagen was extracted from bovine skin and Achilles tendons, and then reconstituted. This was used on burn wounds as dressings after clearance from the Institutional Review Board and Ethics Committees of the Hospital and CLRI. Continued research in this field to enable resulted in the design of silver sulphadiazine loaded alginate microspheres which were embedded in the reconstituted collagen. Controlled delivery of silver sulphadiazine. This collagen membrane was used in chronic infected burns. Low molecular weight heparin was given subcutaneously to improve wound healing in burn injuries and collagen membrane dressings were also applied. After several trials the process technology was patented. The advantages and disadvantages of the collagen membrane cover is elaborated in a group of 487 pediatric burn patients. The trial was conducted at the burn unit of Kanchi Kamakoti Childs Trust Hospital (KKCTH) in Chennai, India. PMID:24133405
Mathangi Ramakrishnan, K.; Babu, M.; Mathivanan; Jayaraman, V.; Shankar, J.
Tendon Driven Finger Actuation System
NASA Technical Reports Server (NTRS)
A humanoid robot includes a robotic hand having at least one finger. An actuation system for the robotic finger includes an actuator assembly which is supported by the robot and is spaced apart from the finger. A tendon extends from the actuator assembly to the at least one finger and ends in a tendon terminator. The actuator assembly is operable to actuate the tendon to move the tendon terminator and, thus, the finger.
Ihrke, Chris A. (Inventor); Reich, David M. (Inventor); Bridgwater, Lyndon (Inventor); Linn, Douglas Martin (Inventor); Askew, Scott R. (Inventor); Diftler, Myron A. (Inventor); Platt, Robert (Inventor); Hargrave, Brian (Inventor); Valvo, Michael C. (Inventor); Abdallah, Muhammad E. (Inventor); Permenter, Frank Noble (Inventor); Mehling, Joshua S. (Inventor)
Open Achilles tendon lacerations.
In contrast to closed Achilles tendon ruptures, open injuries are rarely reported in the literature. This paper provides information about open Achilles tendon wounds that are eventually seen in the Middle East. The reporting unit, Hamad Medical Corporation, is one of the biggest trauma centers in the Gulf area and the major health provider in Qatar. This is a retrospective study including patients admitted and operated for open Achilles tendon injuries between January 2011 and December 2013. Two hundred and five cases of open Achilles tendon lacerations were operated in Hamad General Hospital in this period. Forty-eight cases showed partial injuries, and the remaining are complete tendons cut. In the same period, fifty-one closed ruptured Achilles tendons were operated in the same trauma unit. In the majority of cases, the open injury resulted from a slip in the floor-leveled traditional toilette seats. Local damage to the toilette seats resulted in sharp edges causing the laceration of the heel if the patient was slipping over the wet floor. This occurrence is the cause in the vast majority of the cases. Wounds were located 1-5�cm proximal to tendon insertion. Standard treatment principles were applied. This included thorough irrigation in the emergency room, intravenous antibiotics, surgical debridement and primary repair within 24�h. Patients were kept in the hospital 1-7�days for intravenous antibiotics and possible dressing changes. Postoperatively below knee slabs were applied in the majority of patients and were kept for about 4�weeks followed by gradual weight bearing and range of motion exercises. Outpatients follow up in 1-2�weeks. Further follow-up visits at around 2-, 4-, 8- and 12-week intervals until complete wound healing and satisfactory rehabilitation outcome. Sixteen cases needed a second procedure. A high incidence of Achilles tendon open injuries is reported. This seems to be related to partially damaged floor-level toilettes in the typical Middle-East lavatory. The surgical treatment resulted in excellent outcome in the vast majority of the cases. Low incidence of complications resulted despite dramatic injury pattern. PMID:25337957
Said, M Nader; Al Ateeq Al Dosari, Mohamed; Al Subaii, Nasser; Kawas, Alaa; Al Mas, Ali; Al Ser, Yaser; Abuodeh, Yousef; Shakil, Malik; Habash, Ali; Mukhter, Khalid
Percutaneous Achilles tendon repair
Fourteen patients underwent percutaneous Achilles tendon repairs between 1982 and 1989 for ruptures approximately 2 to 8 cm from the calcaneal insertion. They were evaluated subjectively (questionnaires) and objectively (physical examinations, Cybex II dynamom eter). The minimum follow-up time was 2 years with an average of 3.8 years. Subjectively, all of the patients were satisfied with their overall results. Objectively,
Robert E. Fitzgibbons; John Hefferon; James Hill
Is the Supraspinatus Muscle Atrophy Truly Irreversible after Surgical Repair of Rotator Cuff Tears?
Background Atrophy of rotator cuff muscles has been considered an irreversible phenomenon. The purpose of this study is to evaluate whether atrophy is truly irreversible after rotator cuff repair. Methods We measured supraspinatus muscle atrophy of 191 patients with full-thickness rotator cuff tears on preoperative magnetic resonance imaging and postoperative multidetector computed tomography images, taken at least 1 year after operation. The occupation ratio was calculated using Photoshop CS3 software. We compared the change between pre- and postoperative occupation ratios after modifying the preoperative occupation ratio. In addition, possible relationship between various clinical factors and the change of atrophy, and between the change of atrophy and cuff integrity after surgical repair were evaluated. Results The mean occupation ratio was significantly increased postoperatively from 0.44 � 0.17 to 0.52 � 0.17 (p < 0.001). Among 191 patients, 81 (42.4%) showed improvement of atrophy (more than a 10% increase in occupation ratio) and 33 (17.3%) worsening (more than a 10% decrease). Various clinical factors such as age tear size, or initial degree of atrophy did not affect the change of atrophy. However, the change of atrophy was related to repair integrity: cuff healing failure rate of 48.5% (16 of 33) in worsened atrophy; and 22.2% (18 of 81) in improved atrophy (p = 0.007). Conclusions The supraspinatus muscle atrophy as measured by occupation ratio could be improved postoperatively in case of successful cuff repair. PMID:23467404
Chung, Seok Won; Kim, Sae Hoon; Tae, Suk-Kee; Yoon, Jong Pil; Choi, Jung-Ah
Moist Exposed Burn Ointment (MEBO(�)) is widely used topical agent applied on skin burn. This study investigated the effect of MEBO topical application on activation and proliferation of epidermal stem cells through the immunohistochemical localization of cytokeratin 19 (CK19) as a known marker expressed in epidermal stem cells. Biopsies from normal skin and burn wounds were taken from 21 patients with partial thickness burn 1, 4, 7, 14, 21, and 28 days after treatment with MEBO. Tissue sections were prepared for histological study and for CK19 immunohistochemical localization. In control skin, only few cells showed a positive CK19 immune-reaction. Burned skin showed necrosis of full thickness epidermis that extended to dermis. Gradual regeneration of skin accompanied with an enhancement in CK19 immune-reactivity was noted 4, 7, 14 and 21 days after treatment with MEBO. On day 28, a complete regeneration of skin was observed with a return of CK19 immune-reactivity to the basal pattern again. In conclusion, the enhancement of epidermal stem cell marker CK19 after treatment of partial thickness burn injuries with MEBO suggested the role of MEBO in promoting epidermal stem cell activation and proliferation during burn wound healing. PMID:24576560
El-Hadidy, M R; El-Hadidy, A R; Bhaa, A; Asker, S A; Mazroa, S A
The evidence for application of silver-containing dressings and topicals in the treatment of partial-thickness burns in pediatric patients is largely based on clinical trials involving adult patients despite the important differences between the skin of children and adults. A systematic review and meta-analysis was performed of all randomized controlled trials comparing nonsilver treatment with silver-containing dressings and silver topical agents in children with partial-thickness burns in the acute stage. Endpoints were wound healing, grafting, infection, pain, number of dressing changes, length of hospital stay, and scarring. Seven randomized controlled trials were included involving 473 participants. All trials used silver sulfadiazine as control in comparison with five different nonsilver treatments. Most trials were of moderate quality with high risk of bias. Use of nonsilver treatment led to shorter wound healing time (weighted mean difference: -3.43 days, 95% confidence interval: -4.78, -2.07), less dressing changes (weighted mean difference: -19.89 dressing changes, 95% confidence interval: -38.12, -1.66), and shorter length of hospital stay (weighted mean difference: -2.07 days, 95% confidence interval: -2.63, -1.50) compared with silver sulfadiazine treatment, but no difference in the incidence of wound infection or grafting was found. In conclusion, nonsilver treatment may be preferred over silver sulfadiazine, but high-quality randomized controlled trials are needed to validly confirm the effectiveness of silver containing preparations, in particular silver-containing dressings, above nonsilver treatments. PMID:24899251
Rashaan, Zjir M; Krijnen, Pieta; Klamer, Rachel R M; Schipper, Inger B; Dekkers, Olaf M; Breederveld, Roelf S
Scaffolds in Tendon Tissue Engineering
Tissue engineering techniques using novel scaffold materials offer potential alternatives for managing tendon disorders. Tissue engineering strategies to improve tendon repair healing include the use of scaffolds, growth factors, cell seeding, or a combination of these approaches. Scaffolds have been the most common strategy investigated to date. Available scaffolds for tendon repair include both biological scaffolds, obtained from mammalian tissues, and synthetic scaffolds, manufactured from chemical compounds. Preliminary studies support the idea that scaffolds can provide an alternative for tendon augmentation with an enormous therapeutic potential. However, available data are lacking to allow definitive conclusion on the use of scaffolds for tendon augmentation. We review the current basic science and clinical understanding in the field of scaffolds and tissue engineering for tendon repair. PMID:22190961
Longo, Umile Giuseppe; Lamberti, Alfredo; Petrillo, Stefano; Maffulli, Nicola; Denaro, Vincenzo
Common Disorders of the Achilles Tendon
... helping to raise the heel off the ground. Achilles Tendonitis and Achilles Tendonosis Two common disorders that occur in the heel cord are Achilles tendonitis and Achilles tendonosis. Achilles tendonitis is an inflammation ...
Subluxation of the peroneal tendons is uncommon. It occurs especially in skiing, soccer, basketball, rugby, ice skating, judo, sprint, water-skiing, mountaineering, and gymnastics. We present an overview of the injury, with the classification commonly used. Many surgical techniques have been described to manage recurrent subluxation of the peroneal tendons, but only Level IV/Grade C evidence has been produced. Thus, randomized controlled trials are necessary to determinate the best surgical management method. It appears that high-demand individuals should be primarily managed surgically, and retinaculoplasty seems to be, when indicated, the best surgical option: it affords less complications and a high rate of return to sports without reducing their activity levels. PMID:19440138
Oliva, Francesco; Del Frate, Dario; Ferran, Nicholas Antonio; Maffulli, Nicola
Tenotomy versus Tenodesis in the treatment of the long head of biceps brachii tendon lesions
Background The superiority of tenotomy vs. tenodesis for surgery on lesions of the long head of the biceps brachii tendon is still under debate. Indeed, high-quality evidence is lacking, mainly because of methodological problems, such as retrospective design, population sample size or lack of patient randomization. Methods/Design The study will be a two-center, double-blind, randomized, controlled trial to compare patients treated with biceps tenotomy or tenodesis for lesions of the long head of the biceps brachii tendon over a 2-year follow-up period. The study participants will be 128 adults with biceps brachii tendinopathy and supraspinatus tendon tears. The primary end point will be the postoperative difference in the Constant-Murley score (CMS) between the 2 groups at the two-year follow-up. A comparison of the mean improvement with standard age- and gender-related CMS will be performed. The secondary end point will be evaluation of the postoperative general health of patients, as evaluated with Short Form 36 (SF-36) scores. The number and severity of complications associated with use of the different surgical techniques will be assessed. Discussion This study will be the first randomized and appropriately powered clinical trial to directly compare tenotomy and biceps tenodesis. The results of this study will help to establish clinical practice guidelines for patients suffering from lesions of the long head of the biceps brachii tendon, providing important information to patients and health care providers about the possible complications, outcome predictors and effectiveness of the targeted interventions. Trial Registration Current Controlled Trials ISRCTN38839558 PMID:23088416
The objective of this study was to determine the healing rates of mid-partial-thickness burns treated with a porcine intestinal submucosa (SIS) vs. silver-containing cellulose hydrofiber (AgH) dressings. This was done by comparing healing response of burn wounds treated with SIS vs that of burns treated with AgH dressings. Five patients with mid-partial-thickness burns ?10% of body surface were treated simultaneously, but in different areas, with SIS and AgH dressings; full-thickness biopsies were taken at days 0 and 7. Tissues treated with SIS presented higher epithelial maturation index (6.2 � 0.84 vs. 3.2 � 3.28; [mean � standard deviation], P = .029), better orientation and differentiation of epithelial cells, as well as an appropriate basal lamina structure, collagen deposition, and higher transforming growth factor-?3 expression (7.4 � 8.1 vs. 2.1 � 2.6; P = .055) than tissues treated with AgH dressings. Importantly, after the treatment SIS was not integrated in healed tissues. After 3 months of treatment, SIS produced a lower score according to Vancouver Scar Scale (3.6 � 2.6 vs. 7.2 � 2.5, P = .025).The submucosa dressing does not simply act as scaffolding for the wound, it provides stimulation in the healing area, probably via growth factors initially present in SIS or matrikines derived from its digestion in the wound site. In conclusion, the present study demonstrated that biological matrices favor the wound-healing process. PMID:24823330
Salgado, Rosa M; Bravo, Leonardo; Garc�a, Mario; Melchor, Juan M; Kr�tzsch, Edgar
The author reports the results of a placebo controlled trial of Celestone Chronodose in the treatment of supraspinatus tendinitis involving a total of 180 patients. The results after local injection and deep gluteal injection are also compared. PMID:363484
Valtonen, E J
Flexor tendon injury, repair and rehabilitation.
Injuries to the flexor tendons remain among the most difficult problems in hand surgery. Historically, lacerations to the intrasynovial portion of the flexor tendons were thought to be unsuitable for primary repair. Despite continuing advances in our knowledge of flexor tendon biology, repair, and rehabilitation, good results following primary repair of flexor tendons remain challenging to achieve. PMID:25435036
Lutsky, Kevin F; Giang, Eric L; Matzon, Jonas L
Context: Achilles tendon (AT) rupture in athletes is increasing in incidence and accounts for one of the most devastating sports injuries because of the threat to alter or end a career. Despite the magnitude of this injury, reliable risk assessment has not been clearly defined, and prevention strategies have been limited. The purpose of this review is to identify potential intrinsic and extrinsic risk factors for AT rupture in aerial and ground athletes stated in the current literature. Evidence Acquisition: A MEDLINE search was conducted on AT rupture, or �injury� and �risk factors� and �athletes� from 1980 to 2011. Emphasis was placed on epidemiology, etiology, and review articles focusing on the risk for lower extremity injury in runners and gymnasts. Thirty articles were reviewed, and 22 were included in this assessment. Results: Aerial and ground athletes share many intrinsic risk factors for AT rupture, including overuse and degeneration of the tendon as well as anatomical variations that mechanically put an athlete at risk. Older athletes, athletes atypical in size for their sport, high tensile loads, leg dominance, and fatigue also may increase risk. Aerial athletes tend to have more extrinsic factors that play a role in this injury due to the varying landing surfaces from heights and technical maneuvers performed at various skill levels. Conclusion: Risk assessment for AT rupture in aerial and ground athletes is multivariable and difficult in terms of developing prevention strategies. Quantitative measures of individual risk factors may help identify major contributors to injury. PMID:24427410
Wertz, Jess; Galli, Melissa; Borchers, James R.
Posterior Tibial Tendon Dysfunction (PTTD)
... ACFAS | Informaci�n en Espa�ol Advanced Search Home � Foot & Ankle Conditions � Posterior Tibial Tendon Dysfunction (PTTD) Text Size ... the arch, and an inward rolling of the ankle. As the condition progresses, the symptoms will change. ...
Abstract Background: Deep erythema and inflammation after re-epithelialization of superficial wounds is a sign of scar formation. Corticosteroids may prevent scarring by suppression of inflammation and fibroblast activity. Tretinoin may increase the efficacy of corticosteroids in this setting. Objective: To evaluate the efficacy of corticosteroids plus tretinoin for prevention of scars after superficial wounds. Methods: In a retrospective study of patients with superficial partial thickness thermal skin burn, we compared the patients who received clobetasol plus tretinoin after re-epithelialization with patients who did not receive any medication. Clobetasol propionate 0.05% ointment was used twice daily with overnight occlusive dressing in conjunction with twice weekly topical tretinoin 0.05% cream. Results: Among 43 patients who had light pink or no erythema after re-epithelialization and consequently did not receive clobetasol+tretinoin, no scar was developed. Among patients who had deep erythema after re-epithelialization, rate of scar formation was significantly higher in 14 patients who did not receive clobetasol+tretinoin than in 21 patients who received clobetasol+tretinoin (64% and 19% respectively; P=0.01). Conclusion: Clobetasol+tretinoin can significantly decrease the incidence of scar formation in patients with inflammation after re-epithelialization of superficial wounds. PMID:25424054
Taheri, Arash; Moradi Tuchayi, Sara; Alinia, Hossein; Orscheln, Courtney S; Mansoori, Parisa; Feldman, Steven R
The aim of this study was to evaluate the effectiveness of maintaining the periosteal attachment of the facial and palatal cortical plates on crestal bone loss that occurs at the margin of dental implants placed immediately in split anterior maxillary alveolar ridges. This was a prospective randomized comparative clinical trial. The study population included 22 patients with edentulous anterior maxillary alveolar ridges who presented for treatment during the period March 2012 to September 2013. The selected patients were divided randomly into two equal groups. All patients underwent a maxillary ridge splitting technique; a total of 43 implants were placed immediately. A full thickness mucoperiosteal flap was performed in the control group patients, while a split thickness mucosal flap was done in the study group patients. Assessments included measurements of the linear changes in the marginal bone surrounding the implants immediately postoperative and after 6 months. Measurements were taken from cross-sectional and longitudinal cone beam computed tomography images using special software. The partial thickness flap used in the study group decreased the percentage of bone loss by 9.5% for the labial bone plate, 7.9% for the palatal bone plate, and 3.5% for the mesiodistal bone plate. PMID:24973295
Mounir, M; Beheiri, G; El-Beialy, W
Calcium-phosphate-hybridized tendon directly promotes regeneration of tendon-bone insertion.
We developed a novel technique to improve tendon-bone attachment by hybridizing calcium phosphate (CaP) with tendons using an alternate soaking process. We characterized the deposited CaP on or in tendons and determined the healing process of anterior cruciate ligament (ACL) grafts by implanting CaP-hybridized free tendons in bone tunnels intra-articularly. Tendons to be implanted were alternately soaked 10 times in a Ca-containing solution and a PO(4)-containing solution for 30 s each. Treated tendons had ash contents threefold that of untreated tendons. Low-crystallinity apatite was found on or in treated tendons. In animal experiments, the CaP-hybridized tendon exhibited osteoclasts at the tendon-bone interface at 5 days after operation. At 2 weeks after operation, there were more osteoclasts and osteoblasts around the tendon than at 5 days after operation. Directly bonded areas were partially found between the implanted tendon and newly formed bone. The formation of a cartilage layer was partially apparent at 3 weeks after operation. The newly formed bone was observed almost around the tendon. We conclude that CaP-hybridized tendons clearly enhance the healing process of ACL grafts at the tendon-bone interface and regenerate a direct insertion-like formation of tendons similar to a normal healthy ACL insertion within 3 weeks after operation. PMID:15227677
Mutsuzaki, Hirotaka; Sakane, Masataka; Nakajima, Hiromi; Ito, Atsuo; Hattori, Shinya; Miyanaga, Yutaka; Ochiai, Naoyuki; Tanaka, Junzo
Quadriceps tendon with a patellar bone block may be a viable alternative to Achilles tendon for anterior cruciate ligament reconstruction (ACL-R) if it is, at a minimum, a biomechanically equivalent graft. The objective of this study was to directly compare the biomechanical properties of quadriceps tendon and Achilles tendon allografts. Quadriceps and Achilles tendon pairs from nine research-consented donors were tested. All specimens were processed to reduce bioburden and terminally sterilized by gamma irradiation. Specimens were subjected to a three phase uniaxial tension test performed in a custom environmental chamber to maintain the specimens at a physiologic temperature (37���2��C) and misted with a 0.9�% NaCl solution. There were no statistical differences in seven of eight structural and mechanical between the two tendon types. Quadriceps tendons exhibited a significantly higher displacement at maximum load and significantly lower stiffness than Achilles tendons. The results of this study indicated a biomechanical equivalence of aseptically processed, terminally sterilized quadriceps tendon grafts with bone block to Achilles tendon grafts with bone block. The significantly higher displacement at maximum load, and lower stiffness observed for quadriceps tendons may be related to the failure mode. Achilles tendons had a higher bone avulsion rate than quadriceps tendons (86�% compared to 12�%, respectively). This was likely due to observed differences in bone block density between the two tendon types. This research supports the use of quadriceps tendon allografts in lieu of Achilles tendon allografts for ACL-R. PMID:24414293
Mabe, Isaac; Hunter, Shawn
Partial rupture of the distal biceps tendon.
Partial rupture of the distal biceps tendon is a relatively rare event, and various degrees of partial tendon tears have been reported. In the current study four patients with partial atraumatic distal biceps tendon tears (mean age, 59 years; range, 40-82 years) are reported. In all four patients, a common clinical pattern emerged. Pain at the insertion of the distal biceps tendon in the radius unrelated to any traumatic event was the main symptom. In all patients the diagnosis was based on magnetic resonance imaging or computed tomography imaging. In three of four patients the partial rupture of the tendon caused a significant bursalike lesion. The typical appearance was a partially ruptured biceps tendon, with contrast enhancement signaling the degree of degeneration, tenosynovitis, and soft tissue swelling extending along the tendon semicircular to the proximal radius. In three patients, conservative treatment was successful. Only one patient needed surgery, with reinsertion of the tendon resulting in total functional recovery. PMID:10818980
D�rr, H R; St�bler, A; Pfahler, M; Matzko, M; Refior, H J
Triceps tendon rupture in weight lifters
Triceps tendon avulsion injuries are rare. We report four weight lifters with triceps tendon raptures, two of whom had received local steroid injections for pain in the triceps. All four patients had taken oral anabolic steroids before injury. All patients had closed avulsion of the triceps tendon from its insertion into the olecranon. Three patients were injured while bench pressing
Jonathan L Sollender; Ghazi M Rayan; Glen A Barden
Achilles tendon reflex measuring system
NASA Astrophysics Data System (ADS)
The examination of Achilles tendon reflex is widely used as a simple, noninvasive clinical test in diagnosis and pharmacological therapy monitoring in such diseases as: hypothyroidism, hyperthyroidism, diabetic neuropathy, the lower limbs obstructive angiopathies and intermittent claudication. Presented Achilles tendon reflect measuring system is based on the piezoresistive sensor connected with the cylinder-piston system. To determinate the moment of Achilles tendon stimulation a detecting circuit was used. The outputs of the measuring system are connected to the PC-based data acquisition board. Experimental results showed that the measurement accuracy and repeatability is good enough for diagnostics and therapy monitoring purposes. A user friendly, easy-to-operate measurement system fulfills all the requirements related to recording, presentation and storing of the patients' reflexograms.
Szebeszczyk, Janina; Straszecka, Joanna
Silk and collagen scaffolds for tendon reconstruction.
In this study, silk thread (Bombyx mori) was braided to a tube-like shape and sericin was removed from the silk tube. Thereafter, collagen/chondroitin-6-sulfate solution was poured into the silk tube, and the lyophilization process was performed. To assess the inflammatory response in vivo, raw silk and sericin-free silk tubes were implanted in the subcutaneous layer of mice. After 10 days of in vivo implantation, mild inflammatory responses were observed around the sericin-free silk tubes, and severe inflammation with the presence of neutrophils and macrophages was observed around the raw silk tubes. At 24 weeks post implantation, the regenerated tendon had a thick, cylindrical, grayish fibrous structure and a shiny white appearance, similar to that of the native tendon in the rabbit model of tendon defect. The average tensile strength of the native tendons was 220 � 20 N, whereas the average tensile strength of the regenerated tendons was 167 � 30 N and the diameter of the regenerated tendon (3 � 0.2 mm) was similar to that of the native tendons (4 � 0.3 mm). Histologically, the regenerated tendon resembled the native tendon, and all the regenerated tissues showed organized bundles of crimped fibers. Masson trichrome staining was performed for detecting collagen synthesis, and it showed that the artificial tendon was replaced by new collagen fibers and extracellular matrix. However, the regenerated tendon showed fibrosis to a certain degree. In conclusion, the artificial tendon, comprising a braided silk tube and lyophilized collagen sponge, was optimal for tendon reconstruction. Thus, this study showed an improved regeneration of neo-tendon tissues, which have the structure and tensile strength of the native tendon, with the use of the combination of collagen and silk scaffold. PMID:24705339
Kwon, Soon-Yong; Chung, Jin-Wha; Park, Hee-Jung; Jiang, Yuan-Yuan; Park, Jung-Keug; Seo, Young-Kwon
[Tendinopathy of the gluteus medius tendon].
Tendinopathy of the gluteus medius tendon is the main cause of great trochanter pain syndrom. Recent clinical, ultrasonographic and MRI study, allow to distinguish anterior lesions which concern the lateral part of the gluteus medius tendon, almost always associated with tendinopathy of the gluteus minimus tendon, from tendinopathy of the main tendon of the gluteus medius. Tears of the main tendon of the gluteus medius are the serious disabling consequence of that pathology and must be avoid by early medical and functional treatment with very moderate use of intrabursal corticosteroid injections. In few cases without improvement after medical treatment, surgery is indicated and includes bursectomy of the trochanteric bursa and tendinoplasty. PMID:19462863
Bard, Herv�
Can PRP effectively treat injured tendons?
Summary PRP is widely used to treat tendon and other tissue injuries in orthopaedics and sports medicine; however, the efficacy of PRP treatment on injured tendons is highly controversial. In this commentary, I reason that there are many PRP- and patient-related factors that influence the outcomes of PRP treatment on injured tendons. Therefore, more basic science studies are needed to understand the mechanism of PRP on injured tendons. Finally, I suggest that better understanding of the PRP action mechanism will lead to better use of PRP for the effective treatment of tendon injuries in clinics. PMID:24932445
Wang, James H-C.
The purpose of this study was to determine whether the type of hamstring tendon harvester used can influence harvested tendon characteristics and soft tissue disruption. We compared two different types of tendon harvesters with regard to the length of tendon obtained and soft tissue disruption during hamstring tendon harvesting. Thirty six semitendinosus and gracilis tendons were harvested using either a closed stripper or a blade harvester in 18 paired knees from nine human fresh cadavers. Use of the blade harvester gave longer lengths of usable tendon whilst minimising the stripping of muscle and of any non-usable tendon. Our results suggest that the type of harvester per se can influence the length of tendon harvested as well as soft tissue disruption. Requesting such data from the industry prior to deciding which harvester to use seems desirable. PMID:19272780
Charalambous, C P; Alvi, F; Phaltankar, P; Gagey, O
Although relief of postoperative pain is an imperative aspect of animal welfare, analgesics that do not interfere with the scientific goals of the study must be used. Here we compared the efficacy of different analgesic agents by using an established rat model of supraspinatus tendon healing and a novel gait-analysis system. We hypothesized that different analgesic agents would all provide pain relief in this model but would cause differences in tendon-to-bone healing and gait parameters. Buprenorphine, ibuprofen, tramadol�gabapentin, and acetaminophen were compared with a no-analgesia control group. Gait measures (stride length and vertical force) on the operative forelimb differed between the control group and both the buprenorphine (2 and 4 d postsurgery) and ibuprofen (2 d postsurgery) groups. Step length was different in the control group as compared with the tramadol�gabapentin (2 d after surgery), buprenorphine (2 and 4 d after surgery), and ibuprofen (2 d after surgery) groups. Regarding tendon-to-bone healing, the ibuprofen group showed less stiffness at the insertion site; no other differences in tendon-to-bone healing were detected. In summary, the analgesics evaluated were associated with differences in both animal gait and tendon-to-bone healing. This information will be useful for improving the management of postsurgical pain without adversely affecting tissue healing. Given its ability to improve gait without impeding healing, we recommend use of buprenorphine for postsurgical pain management in rats. In addition, our gait-analysis system can be used to evaluate new analgesics. PMID:24602546
Caro, Adam C; Tucker, Jennica J; Yannascoli, Sarah M; Dunkman, Andrew A; Thomas, Stephen J; Soslowsky, Louis J
Hyperuricemic PRP in tendon cells.
Platelet-rich plasma (PRP) is injected within tendons to stimulate healing. Metabolic alterations such as the metabolic syndrome, diabetes, or hyperuricemia could hinder the therapeutic effect of PRP. We hypothesise that tendon cells sense high levels of uric acid and this could modify their response to PRP. Tendon cells were treated with allogeneic PRPs for 96 hours. Hyperuricemic PRP did not hinder the proliferative actions of PRP. The gene expression pattern of inflammatory molecules in response to PRP showed absence of IL-1b and COX1 and modest expression of IL6, IL8, COX2, and TGF-b1. IL8 and IL6 proteins were secreted by tendon cells treated with PRP. The synthesis of IL6 and IL8 proteins induced by PRP is decreased significantly in the presence of hyperuricemia (P = 0.017 and P = 0.012, resp.). Concerning extracellular matrix, PRP-treated tendon cells displayed high type-1 collagen, moderate type-3 collagen, decorin, and hyaluronan synthase-2 expression and modest expression of scleraxis. Hyperuricemia modified the expression pattern of extracellular matrix proteins, upregulating COL1 (P = 0.036) and COMP (P = 0.012) and downregulating HAS2 (P = 0.012). Positive correlations between TGF-b1 and type-1 collagen (R = 0.905, P = 0.002) and aggrecan (R = 0.833, P = 0.010) and negative correlations between TGF-b1 and IL6 synthesis (R = -0.857, P = 0.007) and COX2 (R = -0.810, P = 0.015) were found. PMID:25276832
Andia, I; Rubio-Azpeitia, E; Maffulli, N
Hyperuricemic PRP in Tendon Cells
Platelet-rich plasma (PRP) is injected within tendons to stimulate healing. Metabolic alterations such as the metabolic syndrome, diabetes, or hyperuricemia could hinder the therapeutic effect of PRP. We hypothesise that tendon cells sense high levels of uric acid and this could modify their response to PRP. Tendon cells were treated with allogeneic PRPs for 96 hours. Hyperuricemic PRP did not hinder the proliferative actions of PRP. The gene expression pattern of inflammatory molecules in response to PRP showed absence of IL-1b and COX1 and modest expression of IL6, IL8, COX2, and TGF-b1. IL8 and IL6 proteins were secreted by tendon cells treated with PRP. The synthesis of IL6 and IL8 proteins induced by PRP is decreased significantly in the presence of hyperuricemia (P = 0.017 and P = 0.012, resp.). Concerning extracellular matrix, PRP-treated tendon cells displayed high type-1 collagen, moderate type-3 collagen, decorin, and hyaluronan synthase-2 expression and modest expression of scleraxis. Hyperuricemia modified the expression pattern of extracellular matrix proteins, upregulating COL1 (P = 0.036) and COMP (P = 0.012) and downregulating HAS2 (P = 0.012). Positive correlations between TGF-b1 and type-1 collagen (R = 0.905, P = 0.002) and aggrecan (R = 0.833, P = 0.010) and negative correlations between TGF-b1 and IL6 synthesis (R = ?0.857, P = 0.007) and COX2 (R = ?0.810, P = 0.015) were found. PMID:25276832
Andia, I.; Rubio-Azpeitia, E.; Maffulli, N.
Subscapularis Tendon Integrity: An Examination of Shoulder Index Tests
Abstract Reference: Hegedus EJ, Goode A, Campbell S, et al. Physical examination tests of the shoulder: a systematic review with meta-analysis of individual tests. Br J Sports Med. 2008;42(2):80�92. Clinical Question: The systematic review focused on various index tests for the shoulder. We concentrated on the subscapularis tendon results to determine the accuracy of reported index tests for clinically diagnosing subscapularis integrity. Data Sources: Studies were identified by an OVID search using MEDLINE, SPORTDiscus, and CINHAL databases (1966�2006) and a hand search by 2 authors (E.J.H. and S.C.). Primary search terms were shoulder, examination, and diagnosis. In addition to the database searches, personal files were hand searched by one of the authors (E.J.H.) for publications, posters, and abstracts. The reference lists in review articles were cross-checked, and all individual names of each special test were queried using MEDLINE and PubMed. Study Selection: The search was limited to English-language journals. Studies were eligible for inclusion if the criterion standard was surgery, magnetic resonance imaging, or injection (subacromial or acromioclavicular joint); at least 1 physical examination test or special test was studied; and one of the paired statistics of sensitivity and specificity was reported or could be determined. Excluded were studies in which the index test was performed under anesthesia or in cadavers, studies in which the index test was assigned the status of composite physical examination, and review articles. Studies were grouped according to the subscapularis index test assessed: lift off, internal-rotation lag sign, Napoleon sign, bear hug, belly off, and belly press. Data Extraction: Studies were selected in a 2-stage process. First, all abstracts and articles found through the search process were independently reviewed by 2 authors (E.J.H. and S.C.). Disagreement on inclusion of an article was resolved by consensus. Second, each selected study was assessed by each reviewer independently. A third reviewer made the final decision on any disagreements for the selected studies. The primary outcome measures were sensitivity and specificity and positive and negative likelihood ratios. The quality of a study was determined by assessing its internal and external validity. Validity was determined by the primary author (E.J.H.) using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) statement. Our work required data extraction from the original articles, which we used to generate 2 � 2 contingency tables for each index test. Pooled indices of clinical usefulness were then determined for each index test. Main Results: The specific search criteria identified 922 articles for review. Of these, 4 met the inclusion and exclusion criteria for subscapularis tendon tears, resulting in the number of studies assessing each index test as follows: 4 for lift off, 2 for internal-rotation lag sign, 2 for Napoleon sign, 1 for bear hug, 1 for belly off, and 1 for belly press. Subscapularis tears were identified by the criterion standard of surgery to visually assess the torn fibers. Across all 4 studies, a total of 304 shoulders were examined, 95 of which had a subscapularis tear (45 full thickness, 50 partial thickness), and 106 were injury free. Indices of clinical usefulness for full-thickness and partial-thickness subscapularis tears are reported in Tables 1 and 2, respectively. PMID:20617916
Rigsby, Ruel; Sitler, Michael; Kelly, John D.
Human tendon behaviour and adaptation, in vivo
Tendon properties contribute to the complex interaction of the central nervous system, muscle�tendon unit and bony structures to produce joint movement. Until recently limited information on human tendon behaviour in vivo was available; however, novel methodological advancements have enabled new insights to be gained in this area. The present review summarizes the progress made with respect to human tendon and aponeurosis function in vivo, and how tendons adapt to ageing, loading and unloading conditions. During low tensile loading or with passive lengthening not only the muscle is elongated, but also the tendon undergoes significant length changes, which may have implications for reflex responses. During active loading, the length change of the tendon far exceeds that of the aponeurosis, indicating that the aponeurosis may more effectively transfer force onto the tendon, which lengthens and stores elastic energy subsequently released during unloading, in a spring-like manner. In fact, data recently obtained in vivo confirm that, during walking, the human Achilles tendon provides elastic strain energy that can decrease the energy cost of locomotion. Also, new experimental evidence shows that, contrary to earlier beliefs, the metabolic activity in human tendon is remarkably high and this affords the tendon the ability to adapt to changing demands. With ageing and disuse there is a reduction in tendon stiffness, which can be mitigated with resistance exercises. Such adaptations seem advantageous for maintaining movement rapidity, reducing tendon stress and risk of injury, and possibly, for enabling muscles to operate closer to the optimum region of the length�tension relationship. PMID:17855761
Magnusson, S Peter; Narici, Marco V; Maganaris, Constantinos N; Kjaer, Michael
Active Achilles tendon kinesitherapy facilitates the functional recovery of a ruptured Achilles tendon. However, protein expression during the healing process remains a controversial issue. New Zealand rabbits, aged 14 weeks, underwent tenotomy followed immediately by Achilles tendon microsurgery to repair the Achilles tendon rupture. The tendon was then immobilized or subjected to postoperative early motion treatment (kinesitherapy). Mass spectrography results showed that after 14 days of motion treatment, 18 protein spots were differentially expressed, among which, 12 were up-regulated, consisting of gelsolin isoform b and neurite growth-related protein collapsing response mediator protein 2. Western blot analysis showed that gelsolin isoform b was up-regulated at days 7�21 of motion treatment. These findings suggest that active Achilles tendon kinesitherapy promotes the neurite regeneration of a ruptured Achilles tendon and gelsolin isoform b can be used as a biomarker for Achilles tendon healing after kinesitherapy. PMID:25317130
Jielile, Jiasharete; Aibai, Minawa; Sabirhazi, Gulnur; Shawutali, Nuerai; Tangkejie, Wulanbai; Badelhan, Aynaz; Nuerduola, Yeermike; Satewalede, Turde; Buranbai, Darehan; Hunapia, Beicen; Jialihasi, Ayidaer; Bai, Jingping; Kizaibek, Murat
Chronic Achilles tendinosis is a condition with unknown aetiology and pathogenesis, most often, but not always, associated with painful nodular thickening of the tendon. In this investigation, 28 tendons (21 patients) with a painful nodule located at the 2-6 cm level in the tendon, and 20 normal (pain-free) tendons, were examined with grey-scale ultrasonography combined with colour Doppler examination. In
Lars �hberg; Ronny Lorentzon; H�kan Alfredson
[Primary flexor tendons repair in zone 2].
Primary flexor tendon repair is still challenging even in the most experienced hands. With atraumatic surgery, the goal is to suture the tendon in a way that it will be strong enough to allow for tendon gliding without the risk of rupture or adhesions during the 12 weeks needed for the tendon to heal. After reviewing the zone 2 anatomy, the authors describe the state of art for flexor tendon repair along with their personal preferences. Although suture methods and postoperative rehabilitation programs are not universal, most specialized teams now use multistrand suturing techniques with at least 4 stands along with protected and controlled early active mobilization. Although the published rates of failure of the repair or postoperative adhesions with stiffness have decreased, these complications are still a concern. They will continue to pose a challenge for scientists performing research into the mechanics and biology of flexor tendon repairs, especially in zone 2. PMID:25442406
Bellem�re, P; Ardouin, L
Management of chronic tendon injuries.
Chronic tendon injuries present unique management challenges. The assumption that these injuries result from ongoing inflammation has caused physicians to rely on treatments demonstrated to be ineffective in the long term. Nonsteroidal anti-inflammatory drugs should be limited in the treatment of these injuries. Corticosteroid injections should be considered for temporizing pain relief only for rotator cuff tendinopathy. For chronic Achilles tendinopathy (symptoms lasting longer than six weeks), an intense eccentric strengthening program of the gastrocnemius/ soleus complex improved pain and function between 60 and 90 percent in randomized trials. Evidence also supports eccentric exercise as a first-line option for chronic patellar tendon injuries. Other modalities such as prolotherapy, topical nitroglycerin, iontophoresis, phonophoresis, therapeutic ultrasound, extracorporeal shock wave therapy, and low-level laser therapy have less evidence of effectiveness but are reasonable second-line alternatives to surgery for patients who have persistent pain despite appropriate rehabilitative exercise. PMID:23547590
Childress, Marc A; Beutler, Anthony
Extensor tendon injuries in athletes.
Extensor tendon injuries of the hand and wrist in high-level athletes can cause a delay in return to play and permanently affect their performance. Given the inherent demand for a speedy and complete recovery, orthopedic surgeons must have an understanding of how to best direct an athlete's treatment for these injuries. The extensor anatomy is very intricate and a thorough understanding of the anatomy can help with both diagnosis and treatment. However, untreated or poorly managed injuries are at risk of leading to chronic deformities. We will discuss the diagnosis and management of the most common extensor tendon injuries and tendinopathies of the hand found in athletes: mallet fingers, swan-neck deformities, boutonniere deformities, central slip ruptures, sagittal band ruptures, intersection syndrome, extensor carpi ulnaris tendinitis, and extensor carpi ulnaris subluxation. PMID:24651290
Chauhan, Aakash; Jacobs, Bruce; Andoga, Alexandra; Baratz, Mark E
Achilles tendon rupture in athletes.
Achilles tendon ruptures commonly affect middle-aged athletes and can result in considerable functional impairment. While the cause is multifactorial, the greatest risk is present for athletes involved in sports that involve sudden acceleration and deceleration. A thorough history and physical examination can accurately yield a diagnosis, but when question remains, magnetic resonance imaging is superior to ultrasound-guided evaluation. The best evidence available suggests that operative treatment has a lower rate of rerupture, a higher rate of return to the same level of sport participation, and a higher complication rate, if an open technique is used. Percutaneous methods of fixation have lower complication rates without an increase in the rate of rerupture when compared with open methods. Augmentation of an Achilles tendon repair has demonstrated no clinical benefit. Rehabilitation with early mobilization leads to improved patient-reported outcomes. PMID:19843435
Deangelis, Joseph P; Wilson, Kristina M; Cox, Charles L; Diamond, Alex B; Thomson, A Brian
Flexor tendon injuries in athletes.
Flexor tendon injuries are not common in most sporting venues; however, recognition of the pertinent anatomy, clinical findings, and the utility of diagnostic imaging will assist the clinician in a thorough evaluation of the athlete's hand. Open injuries demand immediate wound care and evaluation as to the integrity of the flexor apparatus; however, closed injuries often present with the challenges of timing: delayed injury presentation and pressures of intervention and return to play. The purpose of this article is to provide a review of the pertinent anatomy of the flexor apparatus of the hand, to identify key aspects of the patient history, clinical evaluation, and diagnostic testing relevant to flexor function, and to discuss treatment options in the setting of injuries to the flexor tendons and flexor pulley system of the hand. PMID:24651291
Neumann, Julie A; Leversedge, Fraser J
Proximal biceps tendon: injuries and management.
The long head of the biceps tendon is a known pain generator of the shoulder. There are numerous pathologic entities that may affect this tendon, including tendonitis, partial tearing, and subluxation. These conditions are often associated with rotator cuff tears, especially those involving the subscapularis. Operative interventions include tenotomy and tenodesis. Tenodesis can be preformed in a proximal or distal location. Subpectoral tenodesis may have a lower recurrence rate than proximal-based techniques. PMID:18703976
Friedman, Darren J; Dunn, John C; Higgins, Laurence D; Warner, Jon J P
Structure and function of tuna tail tendons.
The caudal tendons in tunas and other scombrid fish link myotomal muscle directly to the caudal fin rays, and thus serve to transfer muscle power to the hydrofoil-like tail during swimming. These robust collagenous tendons have structural and mechanical similarity to tendons found in other vertebrates, notably the leg tendons of terrestrial mammals. Biochemical studies indicate that tuna tendon collagen is composed of the (alpha1)(2),alpha2 heterotrimer that is typical of vertebrate Type I collagen, while tuna skin collagen has the unusual alpha1,alpha2,alpha3 trimer previously described in the skin of some other teleost species. Tuna collagen, like that of other fish, has high solubility due to the presence of an acid-labile intermolecular cross-link. Unlike collagen in mammalian tendons, no differences related to cross-link maturation were detected among tendons in tuna ranging from 0.05 to 72 kg (approx. 0.25-6 years). Tendons excised post-mortem were subjected to load cycling to determine the modulus of elasticity and resilience (mean of 1.3 GPa and 90%, respectively). These material properties compare closely to those of leg tendons from adult mammals that can function as effective biological springs in terrestrial locomotion, but the breaking strength is substantially lower. Peak tendon forces recorded during steady swimming appear to impose strains of much less than 1% of tendon length, and no more than 1.5% during bursts. Thus, the caudal tendons in tunas do not appear to function as elastic storage elements, even at maximal swimming effort. PMID:12485695
Shadwick, Robert E; Rapoport, H Scott; Fenger, Joelle M
Les plaies du tendon patellaire
Les plaies du tendon patellaire sont peu fr�quentes et sont peu rapport�s dans la litt�rature, contrairement aux ruptures sous cutan�es. Les sections du tendon patellaire n�cessitent une r�paration imm�diate afin de r�tablir l'appareil extenseur et de permettre une r�cup�ration fonctionnelle pr�coce. A travers ce travail r�trospectif sur 13 cas, nous analysons les aspects �pid�miologiques, th�rapeutiques et pronostiques de ce type de pathologie en comparant diff�rents scores. L��ge moyen est de 25 ans avec une pr�dominance masculine. Les �tiologies sont domin�es par les accidents de la voie publique (68%) et les agressions par agent tranchant (26%) et contendant (6 %). Tous nos patients ont b�n�fici� d'un parage chirurgical avec suture tendineuse direct prot�g�e par un la�age au fils d'aciers en l�g�re flexion. La r��ducation est d�but�e apr�s s�dation des ph�nom�nes inflammatoires. Au dernier recul les r�sultats sont excellents et bon � 92%. Nous n'avons pas not� de diff�rence de force musculaire et d'amplitude articulaire entre le genou sain et le genou l�s�. Les l�sions ouvertes du tendon patellaire est relativement rare. La prise en charge chirurgicale rapide donne des r�sultats assez satisfaisants. La r�paration est g�n�ralement renforc�e par un semi-tendineux, synth�tique ou m�tallique en forme de cadre de renfort pour faciliter la r�adaptation et r�duire le risque de r�cidive apr�s la fin de l'immobilisation. PMID:25170379
Mechchat, Atif; Elidrissi, Mohammed; Mardy, Abdelhak; Elayoubi, Abdelghni; Shimi, Mohammed; Elibrahimi, Abdelhalim; Elmrini, Abdelmajid
Disorders of the distal biceps brachii tendon.
Pathologic conditions of the distal biceps brachii tendon are of clinical interest, with partial and complete tears being the most common. However, the anatomy of the distal biceps brachii tendon makes imaging of the distal tendon somewhat difficult. An innovation in patient positioning for magnetic resonance (MR) imaging of the distal biceps tendon was recently described in which the patient lies prone with the arm overhead, the elbow flexed to 90 degrees , and the forearm supinated, so that the thumb points superiorly. The acronym FABS (f lexed elbow, abducted shoulder, forearm supinated) has been used to describe this position. The FABS position creates tension in the tendon and minimizes its obliquity and rotation, resulting in a "true" longitudinal view of the tendon. MR imaging and, to a lesser extent, ultrasonography are useful in visualizing the distal tendon and in detecting other pathologic conditions in the cubital fossa. Partial tears are usually characterized by enlargement and abnormal contour of the tendon, along with abnormal intratendinous signal intensity. In complete tears, there is discontinuity and, if the bicipital aponeurosis is also disrupted, retraction. Imaging with FABS positioning can complement conventional MR imaging, especially in the axial plane, in the assessment of the distal biceps tendon. PMID:16160108
Chew, Michael L; Giuffr�, Bruno M
Heterotopic mineralization may result in tendon weakness, but effects on other biomechanical responses have not been reported. We used a needle injury, which accelerates spontaneous mineralization of murine Achilles tendons, to test two hypotheses: that injured tendons would demonstrate altered biomechanical responses; and that unilateral injury would accelerate mineralization bilaterally. Mice underwent left hind (LH) injury (I; n?=?11) and were euthanized after 20 weeks along with non-injured controls (C; n?=?9). All hind limbs were examined by micro computed tomography followed by biomechanical testing (I?=?7 and C?=?6). No differences were found in the biomechanical responses of injured tendons compared with controls. However, the right hind (RH) tendons contralateral to the LH injury exhibited greater static creep strain and total creep strain compared with those LH tendons (p???0.045) and RH tendons from controls (p???0.043). RH limb lesions of injured mice were three times larger compared with controls (p?=?0.030). Therefore, despite extensive mineralization, changes to the responses we measured were limited or absent 20 weeks postinjury. These results also suggest that bilateral occurrence should be considered where tendon mineralization is identified clinically. This experimental system may be useful to study the mechanisms of bilateral new bone formation in tendinopathy and other conditions. PMID:23754538
O'Brien, Etienne John Ogilvy; Shrive, Nigel G; Rosvold, Joshua M; Thornton, Gail M; Frank, Cyril B; Hart, David A
Single-stage reconstruction of flexor tendons with vascularized tendon transfers.
The reconstruction of finger flexor tendons with vascularized flexor digitorum superficialis (FDS) tendon grafts (flaps) based on the ulnar vessels as a single stage is not a popular technique. We reviewed 40 flexor tendon reconstructions (four flexor pollicis longus and 36 finger flexors) with vascularized FDS tendon grafts in 38 consecutive patients. The donor tendons were transferred based on the ulnar vessels as a single-stage procedure (37 pedicled flaps, three free flaps). Four patients required composite tendon and skin island transfer. Minimum follow-up was 12 months, and functional results were evaluated using a total active range of motion score. Multiple linear regression analysis was performed to evaluate the factors that could be associated with the postoperative total active range of motion. The average postoperative total active range of motion (excluding the thumbs) was 178.05� (SD 50�). The total active range of motion was significantly lower for patients who were reconstructed with free flaps and for those who required composite tendon and skin island flap. Age, right or left hand, donor/motor tendon and pulley reconstruction had no linear effect on total active range of motion. Overall results were comparable with a published series on staged tendon grafting but with a lower complication rate. Vascularized pedicled tendon grafts/flaps are useful in the reconstruction of defects of finger flexor tendons in a single stage, although its role in the reconstructive armamentarium remains to be clearly established. PMID:24436359
Cavadas, P C; P�rez-Garc�a, A; Thione, A; Lorca-Garc�a, C
The optimal management of partial flexor tendon laceration is controversial and remains a clinical challenge. Abnormal tendon gliding (triggering and entrapment) was assessed at the A2 pulley in 40 turkey tendons in three groups: intact, partially divided (palmar or lateral), and trimmed. Testing was of gliding resistance and friction coefficient at 30� and 70� of flexion, loaded with 2 and 4 N. We observed for triggering and entrapment. The changes in gliding properties were compared and analysed using Wilcoxon matched pair testing. A significant difference was found in the change in gliding properties of intact to lacerated and lacerated to trimmed tendons and between tendons that glided normally compared with those exhibiting triggering or entrapment. This suggests that palmar and lateral lacerations which, through clinical examination and visualization, are found to glide normally should be treated with early mobilization. However, partial lacerations that exhibit triggering or entrapment should be trimmed. PMID:23735810
Kennedy, J A; Dias, J J
A stainless steel external tendon splint was used in repair of cadaver tendons and compared with standard tendon repairs with suture. The splint was combined with a Kessler repair and tested against the Kessler, Becker, and Savage repairs in fresh human cadaver flexor digitorum profundus tendons. Biomechanical testing was done on a tensile testing machine, and load-displacement curves were generated. The repairs using the external tendon splint demonstrated a range of improvement of 32 to 146% in mean maximal tensile strength and a 20 to 185% improvement of mean ultimate tensile strength compared with all other repairs. The external tendon splint is relatively easy to apply to a tendon. The repair is strengthened and becomes capable of withstanding early active range of motion exercises. In vivo testing will be needed to assess the potential clinical usefulness of such a device. PMID:10672797
Gordon, L; Dysarz, F A; Venkateswara, K T; Mok, A P; Ritchie, R O; Rabinowitz, S
Augmentation of tendon-to-bone healing.
Tendon-to-bone healing is vital to the ultimate success of the various surgical procedures performed to repair injured tendons. Achieving tendon-to-bone healing that is functionally and biologically similar to native anatomy can be challenging because of the limited regeneration capacity of the tendon-bone interface. Orthopaedic basic-science research strategies aiming to augment tendon-to-bone healing include the use of osteoinductive growth factors, platelet-rich plasma, gene therapy, enveloping the grafts with periosteum, osteoconductive materials, cell-based therapies, biodegradable scaffolds, and biomimetic patches. Low-intensity pulsed ultrasound and extracorporeal shockwave treatment may affect tendon-to-bone healing by means of mechanical forces that stimulate biological cascades at the insertion site. Application of various loading methods and immobilization times influence the stress forces acting on the recently repaired tendon-to-bone attachment, which eventually may change the biological dynamics of the interface. Other approaches, such as the use of coated sutures and interference screws, aim to deliver biological factors while achieving mechanical stability by means of various fixators. Controlled Level-I human trials are required to confirm the promising results from in vitro or animal research studies elucidating the mechanisms underlying tendon-to-bone healing and to translate these results into clinical practice. PMID:24647509
Atesok, Kivanc; Fu, Freddie H; Wolf, Megan R; Ochi, Mitsuo; Jazrawi, Laith M; Doral, M Nedim; Lubowitz, James H; Rodeo, Scott A
Ultrasonic evaluation of flood gate tendons
Our water resources infrastructure is susceptible to aging degradation just like the rest of this country`s infrastructure. A critical component of the water supply system is the flood gate that controls the outflow from dams.Long steel rods called tendons attach these radial gates to the concrete in the dam. The tendons are typically forty feet long and over one inch in diameter. Moisture may seep into the grout around the tendons and cause corrosion. Lawrence Livermore National Laboratory is working with the California Department of Water Resources to develop advanced ultrasonic techniques for nondestructively inspecting their tendons. A unique transducer was designed and fabricated to interrogate the entire tendon. A robust,portable unit was assembled that included a computer controlled data acquisition system and specialized data processing software to analyze the ultrasonic signals. This system was tested on laboratory specimens and is presently being fielded at two dam sites.
Thomas, G.; Brown, A.
Treatment of partial distal biceps tendon tears.
Partial rupture of the distal biceps tendon exhibits features similar to that of complete disruption, including acute antecubital pain, weakness of elbow flexion, and forearm supination, and differs only in the fact that the biceps tendon is still palpable in the partial rupture. There are 2 etiologies, first acute traumatic (such as a sudden eccentric contracture) and second, chronic degenerative tendon disease. For accurate diagnosis, a high index of suspicion must be employed. Initial investigations should include plain x-ray and a magnetic resonance scan. Partial tears <50% may be treated with nonoperative management or with surgical debridement of the surrounding synovitis. Tears >50% should be treated with division of the remaining tendon and surgical repair of the entire tendon as a single unit. Surgical endoscopy provides the ability to further quantify the extent of a distal biceps tear and to treat with debridement. This technique, however, should only be used in experienced hands. PMID:18703975
Bain, Gregory I; Johnson, Luke J; Turner, Perry C
Achilles tendon: US diagnosis of pathologic conditions. Work in progress
Twenty-three patients were prospectively examined with ultra-sound (US) for acute or recurrent Achilles tendon symptoms. Three types of pathologic conditions of the Achilles tendon were found: tendinitis/tenosynovitis, acute tendon trauma, and postoperative changes. US appears to enable differentiation of these conditions and to contribute to the diagnosis of a broad range of Achilles tendon disorders.
Blei, C.L.; Nirschl, R.P.; Grant, E.G.
[Peroneal tendons do exist, don't they?].
Peroneal tendon disorders are a significant but often overlooked cause of posterolateral ankle and lateral foot pain. When left untreated, peroneal tendon disorders can lead to persistent pain and substantial functional problems. The goals of this review are to develop a current understanding of the regional anatomy, as well as diagnostic evaluation and current treatment options of the peroneal tendon disorders, and to present nowadays preferred surgical techniques for operative management of peroneal tendon disorders. More specific details related to peroneal tendon luxation, intrasheath subluxation of peroneal tendons, peroneal trendinopathy, peroneal tendon tears and painful os peroneum syndrome are reported in this review article. PMID:25632772
Bojani?, Ivan; Dimnjakovi?, Damjan; Smoljanovi?, Tomislav
Patellar tendonitis and anterior knee pain.
Patellar tendonitis or "jumper's knee" is an important cause of anterior knee pain. The natural history, classification of the lesion, and treatment methods, however, remain controversial. This article presents a retrospective review of 40 patients (50 knees) with various stages of patellar tendonitis and examines the etiology, presentation, clinical picture, investigation, and results of conservative treatment. Twenty-nine men and 11 women ranging in age from 17-48 years comprised the study population. Ten patients had bilateral involvement. The overall evaluation of patients' treatment was 70% with normal or nearly normal results and 30% with abnormal or very abnormal results; most required surgical treatment in the form of arthroscopy, anterior compartment decompression, and patellar tendon exploration. Thirty-seven percent of the patients had a previous history of anterior knee pain (25% had Osgood-Schlatter disease and 12.5% had anterior knee pain). Patellar tendon involvement is appraised according to a new concept. Since patellar tendonitis is part of the wider picture of anterior knee pain, patellar tendonitis is classified as primary or secondary according to presentation, magnetic resonance imaging in general, and the pathology of the patellar tendon in particular. Treatment is planned accordingly. PMID:10323501
Duri, Z A; Aichroth, P M; Wilkins, R; Jones, J
Biological Augmentation of Rotator Cuff Tendon Repair
A histologically normal insertion site does not regenerate following rotator cuff tendon-to-bone repair, which is likely due to abnormal or insufficient gene expression and/or cell differentiation at the repair site. Techniques to manipulate the biologic events following tendon repair may improve healing. We used a sheep infraspinatus repair model to evaluate the effect of osteoinductive growth factors and BMP-12 on tendon-to-bone healing. Magnetic resonance imaging and histology showed increased formation of new bone and fibrocartilage at the healing tendon attachment site in the treated animals, and biomechanical testing showed improved load-to-failure. Other techniques with potential to augment repair site biology include use of platelets isolated from autologous blood to deliver growth factors to a tendon repair site. Modalities that improve local vascularity, such as pulsed ultrasound, have the potential to augment rotator cuff healing. Important information about the biology of tendon healing can also be gained from studies of substances that inhibit healing, such as nicotine and antiinflammatory medications. Future approaches may include the use of stem cells and transcription factors to induce formation of the native tendon-bone insertion site after rotator cuff repair surgery. PMID:18264850
Kovacevic, David
Evidence for the efficacy of extracorporeal shock wave therapy (ESWT) in supraspinatus tendinopathy without calcification is sparse, and therefore this treatment option is often controversial. Patients of a randomized placebo-controlled study to analyze the effects of ESWT on function and pain were revisited 10 years after the initial consultation. The former verum group received 6000 impulses (energy flux density, 0.11 mJ/mm�) in three sessions after local anesthesia between 1999 and 2000. The placebo group had 6000 impulses of a sham ESWT after local anesthesia in the same period. Re-evaluation of the patients included a relative Constant score as well as pain measurements (visual analogue scale) during activity and at rest. No significant changes (p>0.05) in relative Constant scores, pain at rest, or pain during activity could be found after a 10-year follow-up between the placebo and verum groups after ESWT. The treatment of non-calcific supraspinatus tendinopathy with ESWT does not seem to have an effect on function or pain improvement in the long run. The results of the present study cannot advise the use of ESWT in cases of non-calcific supraspinatus tendinopathy. PMID:24728846
Efe, Turgay; Felgentreff, Markus; Heyse, Thomas J; Stein, Thomas; Timmesfeld, Nina; Schmitt, Jan; Roessler, Philip P
Bilateral cadaveric Achilles tendon graft in reconstruction after Achilles tendon tumor resection.
The standard approach to reconstruction after resection of a diffuse-type tenosynovial giant cell tumor is a local patch with free flaps. However, in cases in which the Achilles tendon involvement is extensive, and the entire tendon must be removed, an autologous flap graft might not be adequate to allow a return to function. We report a case of a 52-year-old female patient who developed bilateral tumors of the Achilles tendon, with a 10-year duration. By the time, she sought medical help, both Achilles tendons required removal. We chose to use Achilles tendon allografts to replace the Achilles tendons. Postoperatively, the patient did well. The allograft shortened the recovery time, and the patient regained full ankle range of motion. PMID:22857848
Yang, Maowei; Wang, Zhenpeng; Li, Yuanzhou; Guo, Baolei
Background: Two main factors determine the strength of tendon repair; the tensile strength of material and the gripping capacity of a suture configuration. Different repair techniques and suture materials were developed to increase the strength of repairs but none of techniques and suture materials seem to provide enough tensile strength with safety margins for early active mobilization. In order to overcome this problem tendon suturing implants are being developed. We designed two different suturing implants. The aim of this study was to measure tendon-holding capacities of these implants biomechanically and to compare them with frequently used suture techniques Materials and Methods: In this study we used 64 sheep flexor digitorum profundus tendons. Four study groups were formed and each group had 16 tendons. We applied model 1 and model 2 implant to the first 2 groups and Bunnell and locking-loop techniques to the 3rd and 4th groups respectively by using 5 Ticron sutures. Results: In 13 tendons in group 1 and 15 tendons in group 2 and in all tendons in group 3 and 4, implants and sutures pulled out of the tendon in longitudinal axis at the point of maximum load. The mean tensile strengths were the largest in group 1 and smallest in group 3. Conclusion: In conclusion, the new stainless steel tendon suturing implants applied from outside the tendons using steel wires enable a biomechanically stronger repair with less tendon trauma when compared to previously developed tendon repair implants and the traditional suturing techniques. PMID:25067965
A??r, ?smail; Aytekin, Mahmut Nedim; Ba?�?, Onur; �ayp?nar, Bar??; Erol, B�lent
Decellularized Tendon Extracellular Matrix�A Valuable Approach for Tendon Reconstruction?
Tendon healing is generally a time-consuming process and often leads to a functionally altered reparative tissue. Using degradable scaffolds for tendon reconstruction still remains a compromise in view of the required high mechanical strength of tendons. Regenerative approaches based on natural decellularized allo- or xenogenic tendon extracellular matrix (ECM) have recently started to attract interest. This ECM combines the advantages of its intrinsic mechanical competence with that of providing tenogenic stimuli for immigrating cells mediated, for example, by the growth factors and other mediators entrapped within the natural ECM. A major restriction for their therapeutic application is the mainly cell-associated immunogenicity of xenogenic or allogenic tissues and, in the case of allogenic tissues, also the risk of disease transmission. A survey of approaches for tendon reconstruction using cell-free tendon ECM is presented here, whereby the problems associated with the decellularization procedures, the success of various recellularization strategies, and the applicable cell types will be thoroughly discussed. Encouraging in vivo results using cell-free ECM, as, for instance, in rabbit models, have already been reported. However, in comparison to native tendon, cells remain mostly inhomogeneously distributed in the reseeded ECM and do not align. Hence, future work should focus on the optimization of tendon ECM decellularization and recolonization strategies to restore tendon functionality. PMID:24710540
Schulze-Tanzil, Gundula; Al-Sadi, Onays; Ertel, Wolfgang; Lohan, Anke
Hand surgeons continue to search for the best surgical flexor tendon repair and treatment of the tendon sheaths and pulleys, and they are attempting to establish postoperative regimens that fit diverse clinical needs. It is the purpose of this report to present the current views, methods, and suggestions of six senior hand surgeons from six different countries - all experienced in tendon repair and reconstruction. Although certainly there is common ground, the report presents provocative views and approaches. The report reflects an update in the views of the committee. We hope that it is helpful to surgeons and therapists in treating flexor tendon injuries. PMID:23962872
Tang, Jin Bo; Chang, James; Elliot, David; Lalonde, Donald H; Sandow, Michael; V�gelin, Esther
A disturbance in scapulohumeral rhythm may cause negative biomechanic effects on rotator cuff (RC). Alteration in scapular motion and shoulder pain can influence RC strength. Purpose of this study was to assess supraspinatus and infraspinatus strength in 29 overhead athletes with scapular dyskinesis, before and after 3 and 6 months of rehabilitation aimed to restore scapular musculature balance. A passive posterior soft tissues stretching was prescribed to balance shoulder mobility. Scapular dyskinesis patterns were evaluated according to Kibler et al. Clinical assessment was performed with the empty can (EC) test and infraspinatus strength test (IST). Strength values were recorded by a dynamometer; scores for pain were assessed with VAS scale. Changes of shoulder IR were measured. The force values increased at 3 months (P < 0.01) and at 6 months (P < 0.01). Changes of glenohumeral IR and decrease in pain scores were found at both follow-up. Outcomes registered on pain and strength confirm the role of a proper scapular position for an optimal length-tension relationship of the RC muscles. These data should encourage those caring for athletes to consider restoring of scapular musculature balance as essential part of the athletic training. PMID:21069487
Merolla, Giovanni; De Santis, Elisa; Campi, Fabrizio; Paladini, Paolo; Porcellini, Giuseppe
Primary hydatid disease of the skeletal muscle without systemic involvement is rare. The purpose of this report is to document the novel clinical presentation and the interesting facets of fine-needle aspiration in a case of hydatid disease. It was a case of primary hydatid cyst of the left supraspinatus muscle in an Indian woman living in Kuwait, which was clinically diagnosed as a lipoma. Fine-needle aspiration (FNA) yielded 2 ml of clear fluid with white particulate material. The cytocentrifuged smears prepared from the aspirated fluid showed many scolices, occasional laminated cyst wall fragments and numerous hooklets. The laminated cyst wall and scolices were PAS positive. Trichrome staining imparted a demon-head-like appearance to the scolices. The cytodiagnosis of hydatid cyst was corroborated by histopathological examination of an excised whitish membrane and an irregular cystic fragment, which showed parallel laminations without germinal layer, and skeletal muscle with granulomas and a dense eosinophilic infiltration, respectively. Quantitative serological (indirect hemagglutination) test on blood sample collected 9 days after the excision of the cyst showed insignificant antibody titer to Echinococcus sp. and after 6 weeks the antibodies were completely absent. CT scan of the chest and abdomen performed 7 weeks after removal of cyst showed no evidence of visceral hydatid cyst. PMID:23008130
Das, Dilip K; El-Sharawy, Maha; Ayyash, Emad H; Al-Enezi, Nadia A; Iqbal, Jamshed R; Madda, John P
Tension Distribution in a Tendon-Driven Robotic Finger
NASA Technical Reports Server (NTRS)
A method is provided for distributing tension among tendons of a tendon-driven finger in a robotic system, wherein the finger characterized by n degrees of freedom and n+1 tendons. The method includes determining a maximum functional tension and a minimum functional tension of each tendon of the finger, and then using a controller to distribute tension among the tendons, such that each tendon is assigned a tension value less than the maximum functional tension and greater than or equal to the minimum functional tension. The method satisfies the minimum functional tension while minimizing the internal tension in the robotic system, and satisfies the maximum functional tension without introducing a coupled disturbance to the joint torques. A robotic system includes a robot having at least one tendon-driven finger characterized by n degrees of freedom and n+1 tendons, and a controller having an algorithm for controlling the tendons as set forth above.
Abdallah, Muhammad E. (Inventor); Platt, Robert (Inventor); Wampler, II, Charles W. (Inventor)
In Vivo Identity of Tendon Stem Cells and the Roles of Stem Cells in Tendon Healing
We investigated the spatial distribution of stem cells in tendons and the roles of stem cells in early tendon repair. The relationship between tendon-derived stem cells (TDSCs) isolated in vitro and tendon stem cells in vivo was also explored. Iododeoxyuridine (IdU) label-retaining method was used for labeling stem cells in rat patellar tendons with and without injury. Co-localization of label-retaining cells (LRCs) with different markers was done by immunofluorescent staining. TDSCs were isolated from patellar tendon mid-substance after IdU pulsing, and the expression of different markers in fresh and expanded cells was done by immunofluorescent staining. More LRCs were found at the peritenon and tendon�bone junction compared with the mid-substance. Some LRCs at the peritenon were located at the perivascular niche. The LRC number and the expression of proliferative, tendon-related, pluripotency, and pericyte-related markers in LRCs in the window wound increased. Most of the freshly isolated TDSCs expressed IdU, and some TDSCs expressed pericyte-related markers, which were lost during expansion. Both freshly isolated and subcultured TDSCs expressed pluripotency markers, which were absent in LRCs in intact tendons. In conclusion, we identified LRCs at the peritenon, mid-substance, and tendon�bone junction. There were both vascular and non-vascular sources of LRCs at the peritenon, while the source of LRCs at the mid-substance was non-vascular. LRCs participated in tendon repair via migration, proliferation, activation for tenogenesis, and increased pluripotency. Some LRCs in the window wound were pericyte like. Most of the mid-substance TDSCs were LRCs. The pluripotency markers and pericyte-related marker in LRCs might be important for function after injury. PMID:23815595
Tan, Qi; Lee, Yuk Wa
Laser photoirradiation in digital flexor tendon repair.
This study evaluates tendon coaptation using Nd:YAG laser photoirradiation in an in vivo cockerel model. Using the intervinculum segments of the flexor profundus tendons, experimental transactions were performed. Tendon coaptation was then attempted using laser photoirradiation. Tendons were immediately examined for evidence of stable coaptation. After this assessment, specimens were excised and processed for electron microscopic examination and exposure to trypsin digestion. Despite varying multiple laser parameters, tissue welding was not observed. The subsequent functional and ultrastructural observations of irradiated tendon suggest that these changes are those of simple thermal denaturation. The results of this study suggest that when successful tissue welding has been observed in other tissue types, the mechanism is unlikely to be because of formation of intermolecular collagen bonds as hypothesized. An alternative hypothesis is that laser welding reflects photothermal coagulation of cytoplasmic peptides or nucleic acids liberated at the coaptation interface. This may explain the successful welding of cell-rich tissues such as bowel, vas deferens, and arteries and the observed failure of laser welding in collagen-rich but relatively hypocellular tendon. PMID:11698841
Burt, J D; Siddins, M; Morrison, W A
Posterior tibial tendon dysfunction: a review.
Posterior tibial tendon dysfunction is a progressive deformity that can result in the development of a pathologic flatfoot deformity. Numerous publications have studied the effects of clinical interventions at specific stages of progression of posterior tibial tendon dysfunction, but there is still uncertainty regarding the clinical identification of the condition. It is clear that more information regarding the etiology, progression, and risk factors of posterior tibial tendon dysfunction is required. Clear evidence exists that suggests that the quality of life for patients with posterior tibial tendon dysfunction is significantly affected. Furthermore, evidence suggests that early conservative intervention can significantly improve quality of life regarding disability, function, and pain. This would suggest that significant cost burden reductions could be made by improving awareness of the condition, which would improve early diagnosis. Early conservative intervention may help reduce the number of patients requiring surgery. This review focuses on the etiologic factors, epidemiologic features, and pathogenesis of posterior tibial tendon dysfunction. It aims to analyze, discuss, and debate the current understanding of this condition using the available literature. In addition, there is a discussion of the evidence base surrounding disease characteristics associated with the different clinical stages of posterior tibial tendon dysfunction. PMID:21406702
Durrant, Beverley; Chockalingam, Nachiappan; Hashmi, Farina
Evolution of the Achilles tendon: The athlete's Achilles heel?
The Achilles tendon is believed to have first developed two million years ago enabling humans to run twice as fast. However if the Achilles tendon is so important in terms of evolution, then why is this tendon so prone to injury - especially for those more active like athletes. The Achilles tendon had an integral role in evolving apes from a herbivorous diet to early humans who started hunting for food over longer distances, resulting in bipedal locomotion. Evolutionary advantages of the Achilles tendon includes it being the strongest tendon in the body, having an energy-saving mechanism for fast locomotion, allows humans to jump and run, and additionally is a spring and shock absorber during gait. Considering these benefits it is therefore not surprising that studies have shown athletes have thicker Achilles tendons than subjects who are less active. However, contradictory to these findings that show the importance of the Achilles tendon for athletes, it is well known that obtaining an Achilles tendon injury for an athlete can be career-altering. A disadvantage of the Achilles tendon is that the aetiology of its pathology is complicated. Achilles tendon ruptures are believed to be caused by overloading the tensed tendon, like during sports. However studies have also shown athlete Achilles tendon ruptures to have degenerative changes in the tendon. Other flaws of the Achilles tendon are its non-uniform vascularity and incomplete repair system which may suggest the Achilles tendon is on the edge of evolution. Research has shown that there is a genetic influence on the predisposition a person has towards Achilles tendon injuries. So if this tendon is here to stay in our anatomy, and it probably is due to the slow rate of evolution in humans, research in genetic modification could be used to decrease athletes' predisposition to Achilles tendinopathy. PMID:21900004
Malvankar, S; Khan, W S
Patellar tendon shortening after anterior cruciate ligament reconstruction may be associated with anterior knee pain or patellofemoral arthritis. The present study was designed to compare postoperative changes in patellar tendon length after anterior cruciate ligament reconstruction between patellar tendon and hamstring tendon autograft. Magnetic resonance images of both knees (operated and healthy) and functional outcome were documented at least 1 year postoperatively in 16 patellar tendon harvested patients and in 32 hamstrings harvested patients. Patellar tendon length, patella length and Insall-Salvati ratio were measured. The operated knee values were compared to the respective values of the non-operated control knees. A significant 4.2 mm or 9.7% patellar tendon shortening in patellar tendon group and a non-significant 1.14 mm or 2.6% shortening in hamstrings group was detected. No significant difference was detected in terms of major shortening-patella baja-(6% for the patellar tendon group vs. 0% for the hamstring group). There was no significant difference in anterior knee problems between the two groups as evidenced by the Shelbourne score (94 for the patellar tendon group vs. 98 for the hamstring group). Harvesting of the patellar tendon for anterior cruciate ligament reconstruction resulted in a significant shortening of the remaining tendon. In contrast harvesting of the hamstring tendons did not affect significantly the patellar tendon length. However, the incidence of patella baja and overall functional outcome was not significantly different between the two groups. PMID:17225175
Hantes, Michael E; Zachos, Vasilios C; Bargiotas, Konstantinos A; Basdekis, Georgios K; Karantanas, Apostolos H; Malizos, Konstantinos N
Tendon and ligament injuries are common causes of impaired performance in equine athletes. Gray-scale ultrasonography is the current standard method for diagnosing and monitoring these injuries, however this modality only provides morphologic information. Elastography is an ultrasound technique that allows detection and measurement of tissue strain, and may provide valuable mechanical information about equine tendon and ligament injuries. The purpose of this study was to determine the feasibility, reproducibility, and repeatability of elastography; and to describe elastographic characteristics of metacarpal tendons in sound horses. Nineteen legs for 17 clinically sound horses without evidence of musculoskeletal pathology were included. Elastographic images of the superficial and deep digital flexor tendons and the branches of the suspensory ligament (tendon of the interosseous muscle) were described quantitatively and qualitatively. There was no statistically significant difference between operators (P = 0.86) nor within operators (P = 0.93). For qualitative assessments, reproducibility (0.46) was moderate and repeatability (0.78) was good. Similar to human Achilles tendons, equine tendons were classified as predominantly hard using elastography. There was no statistically significant difference in stiffness of the flexor tendons (P = 0.96). No significant difference in stiffness was found with altered leg position during standing (P = 0.84) and while nonweight bearing (P = 0.61). The flexor tendons were softer when imaged in longitudinal versus transverse planes (P < 0.01) however, the suspensory branches were not (P = 0.67). Findings supported future clinical application of elastography as a noninvasive "stall-side" imaging modality for evaluation of the tendons and ligaments of the distal forelimb in horses. PMID:24103015
Lustgarten, Meghann; Redding, W Rich; Labens, Raphael; Morgan, Michel; Davis, Weston; Seiler, Gabriela S
21 CFR 888.3025 - Passive tendon prosthesis.
Code of Federal Regulations, 2014 CFR
...Passive tendon prosthesis. (a) Identification. A passive tendon prosthesis is a device intended to be implanted made of silicon elastomer or a polyester reinforced medical grade silicone elastomer intended for use in the surgical...
21 CFR 888.3025 - Passive tendon prosthesis.
Code of Federal Regulations, 2012 CFR
...Passive tendon prosthesis. (a) Identification. A passive tendon prosthesis is a device intended to be implanted made of silicon elastomer or a polyester reinforced medical grade silicone elastomer intended for use in the surgical...
21 CFR 888.3025 - Passive tendon prosthesis.
Code of Federal Regulations, 2011 CFR
... (a) Identification. A passive tendon prosthesis is a device intended to be implanted made of silicon elastomer or a polyester reinforced medical grade silicone elastomer intended for use in the surgical reconstruction of a flexor tendon of...
Structure-function relationships in tendons: a review
The purpose of the current review is to highlight the structure-function relationship of tendons and related structures to provide an overview for readers whose interest in tendons needs to be underpinned by anatomy. Because of the availability of several recent reviews on tendon development and entheses, the focus of the current work is primarily directed towards what can best be described as the �tendon proper� or the �mid-substance� of tendons. The review covers all levels of tendon structure from the molecular to the gross and deals both with the extracellular matrix and with tendon cells. The latter are often called �tenocytes� and are increasingly recognized as a defined cell population that is functionally and phenotypically distinct from other fibroblast-like cells. This is illustrated by their response to different types of mechanical stress. However, it is not only tendon cells, but tendons as a whole that exhibit distinct structure-function relationships geared to the changing mechanical stresses to which they are subject. This aspect of tendon biology is considered in some detail. Attention is briefly directed to the blood and nerve supply of tendons, for this is an important issue that relates to the intrinsic healing capacity of tendons. Structures closely related to tendons (joint capsules, tendon sheaths, pulleys, retinacula, fat pads and bursae) are also covered and the concept of a �supertendon� is introduced to describe a collection of tendons in which the function of the whole complex exceeds that of its individual members. Finally, attention is drawn to the important relationship between tendons and fascia, highlighted by Wood Jones in his concept of an �ectoskeleton� over half a century ago � work that is often forgotten today. PMID:18304204
Benjamin, M; Kaiser, E; Milz, S
An Overview of the Management of Flexor Tendon Injuries
Flexor tendon injuries still remain a challenging condition to manage to ensure optimal outcome for the patient. Since the first flexor tendon repair was described by Kirchmayr in 1917, several approaches to flexor tendon injury have enabled successful repairs rates of 70-90%. Primary surgical repair results in better functional outcome compared to secondary repair or tendon graft surgery. Flexor tendon injury repair has been extensively researched and the literature demonstrates successful repair requires minimal gapping at the repair site or interference with tendon vascularity, secure suture knots, smooth junction of tendon end and having sufficient strength for healing. However, the exact surgical approach to achieve success being currently used among surgeons is still controversial. Therefore, this review aims to discuss the results of studies demonstrating the current knowledge regarding the optimal approach for flexor tendon repair. Post-operative rehabilitation for flexor tendon surgery is another area, which has caused extensive debate in hand surgery. The trend to more active mobilisation protocols seems to be favoured but further study in this area is needed to find the protocol, which achieves function and gliding but avoids rupture of the tendons. Lastly despite success following surgery complications commonly still occur post surgery, including adhesion formation, tendon rupture and stiffness of the joints. Therefore, this review aims to discuss the appropriate management of these difficulties post surgery. New techniques in management of flexor tendon will also be discussed including external laser devices, addition of growth factors and cytokines. PMID:22431948
Griffin, M; Hindocha, S; Jordan, D; Saleh, M; Khan, W
In vivo achilles tendon loading' during jumping in humans
Elastic behaviour of the human tendomuscular system during jumping was investigated by determination of the in vivo Achilles tendon force. A buckle-type transducer was implanted under local anaesthesia around the right Achilles tendon of an adult subject. After calibration, the Achilles tendon force was recorded together with the triceps surae muscle electromyogram activity and high speed filming and ground reaction
Senshi Fukashiro; Paavo V. Komi; Markku J�rvinen; Mitsumasa Miyashita
Biodegradable synthetic scaffolds for tendon regeneration
Summary Tissue regeneration is aimed at producing biological or synthetic scaffolds to be implanted in the body for regenerate functional tissues. Several techniques and materials have been used to obtain biodegradable synthetic scaffolds, on which adhesion, growth, migration and differentiation of human cells has been attempted. Scaffolds for tendon regeneration have been less frequently proposed, because they have a complex hierarchical structure and it is very difficult to mimic their peculiar mechanical properties. In this review, we critically analyzed the proposed materials and fabrication techniques for tendon tissue engineering and we indicated new preparation processes, based on the use of supercritical fluids, to produce scaffolds with characteristics very similar to the native tendon structure. PMID:23738295
Reverchon, Ernesto; Baldino, Lucia; Cardea, Stefano; De Marco, Iolanda
Structure-strength relations in mammalian tendon.
The stress-strain relations in mammalian tendon are analyzed in terms of the structure and mechanics of its constituents. The model considers the tensile and bending strength of the collagen fibers, the tensile strength of the elastin fibers, and the interaction between the matrix and the collagen fibers. The stress-strain relations are solved through variational considerations by assuming that the fibermaxtrix interactions can be modeled as beam on elastic foundation. The tissue thus modeled is a hyperelastic material. It is further shown that on the basis of the model, the dominant parameters to the tendon's behavior can be evaluated from simple tensile tests. PMID:728528
Lanir, Y
Proximal biceps tendon tear in an adolescent tennis player.
The diagnosis of a torn biceps tendon in athletes who use overhead throwing or swinging motions can be difficult to make because there is no one physical examination finding that will confirm the diagnosis, and because magnetic resonance imaging, although sometimes helpful, does not image the length of the biceps tendon adequately. We report a case of an isolated partial biceps tendon tear in an adolescent female athlete who was diagnosed during arthroscopy after the tendon was pulled into the joint. The tendon was cut and a tenodesis was performed. Two years after the surgical procedure, the patient was without pain and returned to playing tennis at her previous level. PMID:23527332
Johnson, Alan R; Higgins, Brendan T; Teixeira, Rafael P; Garzon-Muvdi, Juan; McFarland, Edward G
The role of animal models in tendon research
Tendinopathy is a debilitating musculoskeletal condition which can cause significant pain and lead to complete rupture of the tendon, which often requires surgical repair. Due in part to the large spectrum of tendon pathologies, these disorders continue to be a clinical challenge. Animal models are often used in this field of research as they offer an attractive framework to examine the cascade of processes that occur throughout both tendon pathology and repair. This review discusses the structural, mechanical, and biological changes that occur throughout tendon pathology in animal models, as well as strategies for the improvement of tendon healing. Cite this article: Bone Joint Res 2014;3:193�202. PMID:24958818
Hast, M. W.; Zuskov, A.; Soslowsky, L. J.
Spontaneous "spaghetti" flexor tendon ruptures in the rheumatoid wrist.
A 54-year-old woman who had been treated for rheumatoid arthritis for 12 years developed spontaneous multiple flexor tendon ruptures during a 5-month period. Radiography revealed volar subluxation of the lunate bone. Surgery was performed 5 months after the first onset of tendon rupture. All eight flexors, except the flexor pollicis longus tendons, had ruptured, and the damage resembled spaghetti. Four flexor digitorum profundus tendons were reconstructed by bridge graft using their respective sublimis tendons. Wrist joint fusion and tenolysis were performed 3 months after the first operation. Each finger achieved a good range of motion 2 years and 6 months after the second operation. PMID:17143686
Hashizume, Hiroyuki; Nishida, Keiichiro; Fujiwara, Kazuo; Inoue, Hajime
Relationship between compressive loading and ECM changes in tendons
Summary Tendons are designed to absorb and transfer large amounts of tensile load. The well organised, strong yet flexible, extracellular matrix allows for this function. Many tendons are also subject to compressive loads, such as at the entheses, as the tendon wraps around bony protuberances or from internal compression during tensile loading or twisting. Tendinopathy, the clinical syndrome of pain and dysfunction in a tendon is usually the result of overload. However, it is not only the tensile overload that should be considered, as it has been shown that compressive loads change tendon structure and that combination loads can induce tendon pathology. This review summarises how load is detected by the tenocytes, how they respond to compressive load and the resulting extracellular matrix changes that occur. Understanding the effect of compression on tendon structure and function may provide directions for future matrix based interventions. PMID:23885340
Docking, Sean; Samiric, Tom; Scase, Ebonie; Purdam, Craig; Cook, Jill
We report a case of simultaneous reconstruction of a quadriceps tendon rupture after total knee arthroplasty (TKA) and neglected Achilles tendon rupture, which occurred before TKA with an ipsilateral hamstring autograft. A 64-year-old woman presented with persistent right knee pain. She also had right heel pain and had received multiple steroid injections at the knee joint and heel. On examination, she showed osteoarthritis in the medial and lateral compartments of the knee joint and an Achilles tendon rupture in the ipsilateral limb. There was skin dimpling and the proximal portion of tendon was migrated. We performed TKA, and the postoperative course was satisfactory. She returned 3 months postoperatively, however, with skin dimpling around the suprapatellar area and weakness of knee extension. Her ankle symptoms were also aggravated because she could not use the knee joint freely. We performed simultaneous reconstruction of the quadriceps tendon and the Achilles tendon using an ipsilateral hamstring autograft.Hamstring autograft offers a good alternative treatment option for rupture repair, particularly with concommitant ruptures of multiple sites when primary repair is not possible or the viability of repaired tissue is poor. PMID:20506939
Lee, Yong Seuk; Min, Byoung-Hyun; Han, Kyeong-Jin; Cho, Jae Ho; Han, Seung Hwan; Lee, Doo-Hyung; Oh, Kyung Soo
Functional postoperative treatment of Achilles tendon repair
Twenty-one patients with surgically repaired Achilles tendon tears that were treated postoperatively with a functional orthosis rather than routine cast immobiliza tion were evaluated. The orthosis allowed unrestricted plantar flexion and limited dorsiflexion to neutral. Toe- touch weightbearing crutch ambulation was allowed immediately and was gradually increased over the 6 to 8 weeks of treatment. Of the 21 patients, 14
Thomas R. Carter; Peter J. Fowler; Cathy Blokker
Spondylodiscitis and Achilles tendonitis due to gout.
The patient, a 62-year-old man with a 3-year history of hyperuricemia, presented with severe neck pain, Achilles enthesopathy and polyarthralgia. He consumed alcohol heavily. The biochemical profile was normal except for elevated levels of CRP (3.6 mg/dl; normal < 0.3), uric acid (UA) (10.9 mg/dl; normal 2.5-7.5) and creatinine (1.7 mg/dl; normal 0.5-1.0). Bone scintigraphy showed polyarthritis at the right elbow, wrist and bilateral first MTP joints. Notably, bone scintigraphy with computed tomography also revealed spondylodiscitis of C5-C6, which was confirmed by MRI, and left Achilles tendonitis. Moreover, left Achilles tendonitis was also confirmed by ultrasonography, indicating enthesitis with low-echoic lesion and calcification. Needle aspiration yielded a white viscous liquid, with numerous urate crystals identified on polarized light microscopy. He was diagnosed with gouty arthritis associated with spondylodiscitis and Achilles tendonitis. After the treatment with allopurinol, colchicine and predonisolone, his symptoms were improved, and serum CRP and UA levels were normalized. The cervical spine and Achilles tendon are rare and notable sites of involvements in gout, and differential diagnosis of gouty arthritis from spondyloarthritis, rheumatoid arthritis, tumor, pseudogout, and infection is necessary. When the patient was noted to have neck pain and Achilles enthesopathy, we should always recognize gouty arthritis. PMID:24498865
Taniguchi, Yoshinori; Matsumoto, Tatsuki; Tsugita, Makoto; Fujimoto, Shimpei; Terada, Yoshio
Engaging Stem Cells for Customized Tendon Regeneration
The need for a consistent therapeutic approach to tendon injury repair is long overdue. Patients with tendon microtears or full ruptures are eligible for a wide range of invasive and non invasive interventions, often subjectively decided by the physician. Surgery produces the best outcomes, and while studies have been conducted to optimize graft constructs and to track outcomes, the data from these studies have been inconclusive on the whole. What has been established is a clear understanding of healthy tendon architecture and the inherent process of healing. With this knowledge, tissue regeneration efforts have achieved immense progress in scaffold design, cell line selection, and, more recently, the appropriate use of cytokines and growth factors. This paper evaluates the plasticity of bone-marrow-derived stem cells and the elasticity of recently developed biomaterials towards tendon regeneration efforts. Mesenchymal stem cells (MSCs), hematopoietic progenitor cells, and poly(1,8-octanediol co-citrate) scaffolds (POC) are discussed in the context of established grafting strategies. With POC scaffolds to cradle the growth of MSCs and hematopoietic progenitor cells, developing a fibroelastic network guided by cytokines and growth factors may contribute towards consistent graft constructs, enhanced functionality, and better patient outcomes. PMID:22685473
Thaker, Hatim; Sharma, Arun K.
How tendons buffer energy dissipation by muscle
To decelerate the body and limbs, muscles actively lengthen to dissipate energy. During rapid energy-dissipating events, tendons buffer the work done on muscle by temporarily storing elastic energy, then releasing this energy to do work on the muscle. This elastic mechanism may reduce the risk of muscle damage by reducing peak forces and lengthening rates of active muscle. PMID:23873133
Roberts, Thomas J.; Konow, Nicolai
On muscle, tendon and high heels.
Wearing high heels (HH) places the calf muscle-tendon unit (MTU) in a shortened position. As muscles and tendons are highly malleable tissues, chronic use of HH might induce structural and functional changes in the calf MTU. To test this hypothesis, 11 women regularly wearing HH and a control group of 9 women were recruited. Gastrocnemius medialis (GM) fascicle length, pennation angle and physiological cross-sectional area (PCSA), the Achilles' tendon (AT) length, cross-sectional area (CSA) and mechanical properties, and the plantarflexion torque-angle and torque-velocity relationships were assessed in both groups. Shorter GM fascicle lengths were observed in the HH group (49.6+/-5.7 mm vs 56.0+/-7.7 mm), resulting in greater tendon-to-fascicle length ratios. Also, because of greater AT CSA, AT stiffness was higher in the HH group (136.2+/-26.5 N mm(-1) vs 111.3+/-20.2 N mm(-1)). However, no differences in the GM PCSA to AT CSA ratio, torque-angle and torque-velocity relationships were found. We conclude that long-term use of high-heeled shoes induces shortening of the GM muscle fascicles and increases AT stiffness, reducing the ankle's active range of motion. Functionally, these two phenomena seem to counteract each other since no significant differences in static or dynamic torques were observed. PMID:20639419
Csapo, R; Maganaris, C N; Seynnes, O R; Narici, M V
Versican splice variant messenger RNA expression in normal human Achilles tendon and tendinopathies
Objectives. Versican is the principal large proteoglycan expressed in mid-tendon, but its role in tendon pathology is unknown. Our objective was to define the expression of versican isoform splice variant messenger ribonucleic acid (mRNA) in normal Achilles tendons, in chronic painful tendinopathy and in ruptured tendons. Methods. Total RNA isolated from frozen tendon samples (normal n � 14; chronic painful
A. N. Corps; A. H. N. Robinson; T. Movin; M. L. Costa; D. C. Ireland; B. L. Hazleman; G. P. Riley
Effect of tendon tensioning: an in vitro study in porcine extensor tendons.
Graft tensioning is a controversial issue in anterior cruciate ligament reconstruction (ACLR) that has not achieved consensus between peers. The purpose of this study is to determine if after tensioning tendon length and resistance to maximal load changes. We performed an in vitro study with 50 porcine extensors tendons. The first group (P=25) was tensioned with 80 N (19.97 lb) for 10 min, using an ACL graft preparation board. The second group (C=25) was used as control and was not tensioned. The average initial (groups P and C) and post tensioning tendon length (group C) were measured; the average initial and post tensioning tendon diameter were measured as well. All samples were fixated in a tube-clamp system connected to a tension sensor. The samples were stressed with continuous and progressive tension until ultimate failure at maximum load (UFML) occurs. The initial mean length was: P before tensioning=13.4 mm+/-1.4 mm (range 10.5-16.5); P after tensioning=13.8 mm+/-1.4 mm (range 11.5-16.5); C=13 mm+/-1.35 mm (p=0.005). The mean diameter was: P=5.6 mm (4.5-6); C=5.5 mm (range 4.5-6) (p>0.05). The UFML was: P=189.7 N (114-336); C=229.9 N (143-365) (p=0.029). Tendon tensioning with 80 N for 10 min produced 3% average elongation. These could be beneficial in ACLR since tendon tensioning decreases elongation of the graft after fixation. Regardless, tendon tensioning is not innocuous since it diminishes their resistance when continuously stressed until complete failure occurs. PMID:19744857
Figueroa, David; Calvo, Rafael; Vaisman, Alex; Mele�n, Patricio; Figueroa, Francisco
The aim of this study was to investigate the association between foot type and the morphometry of selected muscles and tendons of the lower limb. Sixty-one healthy participants (31 male, 30 female; aged 27.1 � 8.8 years) underwent gray-scale musculoskeletal ultrasound examination to determine the anterior-posterior (AP) thickness of tibialis anterior, tibialis posterior, and peroneus longus muscles and tendons as well as the Achilles tendon. Foot type was classified based on arch height and footprint measurements. Potentially confounding variables (height, weight, hip and waist circumference, rearfoot and ankle joint range of motion, and levels of physical activity) were also measured. Multiple linear regression models were used to determine the association between foot type with muscle and tendon morphometry accounting for potentially confounding variables. Foot type was significantly and independently associated with AP thickness of the tibialis anterior tendon, peroneus longus muscle, and Achilles tendon, accounting for approximately 7% to 16% of the variation. Flat-arched feet were associated with a thicker tibialis anterior tendon, a thicker peroneus longus muscle, and a thinner Achilles tendon. Foot type is associated with morphometry of tendons that control sagittal plane motion of the rearfoot; and the peroneus longus muscle that controls frontal plane motion of the rearfoot. These findings may be related to differences in tendon loading during gait. PMID:23301865
Murley, G S; Tan, J M; Edwards, R M; De Luca, J; Munteanu, S E; Cook, J L
To compare the excursion efficiency and moment arms of flexor digitorum superficialis (FDS) and profundus (FDP) among different conditions of pulley integrity related to trigger finger treatment, cadaveric fingers were first tested with an intact pulley system, and then the first (A1) and second (A2) annular pulleys were released gradually from the proximal to distal part. Linear position sensors and a motion capture system were used to measure the tendon excursion and joint rotation simultaneously. The tendon excursion efficiency was defined as the range of motion of the involved joints per unit of tendon excursion, and the tendon moment arm was determined by the slope of the linear fitting result of tendon excursion versus metacarpophalangeal (MCP) joint rotation. No significant differences were found between the release of the A1 pulley and the release extending to half the proximal part of the A2 pulley in the FDP excursion efficiency and the moment arms of FDS and FDP with respect to the MCP joint. These results imply that the release could extend to half the proximal A2 pulley, if necessary, without significantly decreasing the FDP excursion efficiency and increasing the moment arms of FDS and FDP with respect to the MCP joint. � 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:224-228, 2015. PMID:25297915
Lu, Szu-Ching; Yang, Tai-Hua; Kuo, Li-Chieh; Jou, I-Ming; Sun, Yung-Nien; Su, Fong-Chin
Imaging the infrapatellar tendon in the elite athlete.
Extensor mechanism injuries constitute a major cause of anterior knee pain in the elite athlete. Sonography and magnetic resonance imaging (MRI) are the imaging methods of choice when assessing the infrapatellar tendon. A comprehensive imaging review of infrapatellar tendon normal anatomy, tendinopathy, and partial/full-thickness tendon tears is provided. The value of imaging the infrapatellar tendon in clinical practice, including whether sonography can predict symptoms in asymptomatic athletes, is discussed. Acute avulsion fractures, including periosteal sleeve avulsion, and chronic avulsion injuries, including Sinding-Larsen-Johansson and Osgood-Schlatter syndromes, are shown. Mimics of infrapatellar tendon pathology, including infrapatellar plica injury, patellar tendon-lateral femoral condyle friction syndrome, and Hoffa's syndrome, are illustrated. PMID:16784942
Peace, K A L; Lee, J C; Healy, J
The Achilles tendon: fundamental properties and mechanisms governing healing
Summary This review highlights recent research on Achilles tendon healing, and comments on the current clinical controversy surrounding the diagnosis and treatment of injury. The processes of Achilles tendon healing, as demonstrated through changes in its structure, composition, and biomechanics, are reviewed. Finally, a review of tendon developmental biology and mechano transductive pathways is completed to recognize recent efforts to augment injured Achilles tendons, and to suggest potential future strategies for therapeutic intervention and functional tissue engineering. Despite an abundance of clinical evidence suggesting that current treatments and rehabilitation strategies for Achilles tendon ruptures are equivocal, significant questions remain to fully elucidate the basic science mechanisms governing Achilles tendon injury, healing, treatment, and rehabilitation. PMID:25332943
Freedman, Benjamin R.; Gordon, Joshua A.; Soslowsky, Louis J.
Exploring the application of stem cells in tendon repair and regeneration.
clinical studies met the inclusion criteria. Preclinical studies have shown that stem cells are able to survive and differentiate into tendon cells when placed into a new tendon environment, leading to regeneration and biomechanical benefit to the tendon...
Ahmad, Z; Wardale, J; Brooks, R; Henson, F; Noorani, A; Rushton, N
Federal Register 2010, 2011, 2012, 2013, 2014
...Prestressed Concrete Containment Structures With Grouted Tendons AGENCY...Prestressed Concrete Containment Structures with Grouted Tendons...prestressed concrete containment structures with grouted tendons. ADDRESSES...postulated accidents, and data that the staff needs in...
Anterior cruciate ligament reconstruction with allograft tendons.
Allograft tissue allows reconstruction of the ACL without the donor site morbidity that can be caused by autograft harvesting. Patients who must kneel as a part of their occupation or chosen sport are particularly good candidates for allograft reconstruction. Patients over 45 years of age and those requiring revision ACL surgery can also benefit from the use and availability of allograft tendons. In some cases, patients or surgeons may opt for allograft tendons to maximize the result or morbidity ratio. Despite advances in cadaver screening and graft preparation, there remain risks of disease transmission and joint infection after allograft implantation. Detailed explanation and informed consent is vitally important in cases in which allograft tissue is used. PMID:12735200
Strickland, Sabrina M; MacGillivray, John D; Warren, Russell F
Percutaneous & Mini Invasive Achilles tendon repair
Rupture of the Achilles tendon is a considerable cause of morbidity with reduced function following injury. Recent studies have shown little difference in outcome between the techniques of open and non-operative treatment using an early active rehabilitation programme. Meta-analyses have shown that non-operative management has increased risk of re-rupture whereas surgical intervention has risks of complications related to the wound and iatrogenic nerve injury. Minimally invasive surgery has been adopted as a way of reducing infections rates and wound breakdown however avoiding iatrogenic nerve injury must be considered. We discuss the techniques and outcomes of percutaneous and minimally invasive repairs of the Achilles tendon. PMID:22082172
Biomechanical Analysis of Distal Biceps Tendon Repair Methods
Background: The 1-incision and 2-incision techniques are commonly used methods to repair a distal biceps rupture, and they differ in the location of reinsertion of tendon into bone.Hypothesis: The native distal biceps brachii tendon inserts on the posterior-ulnar aspect of the bicipital tuberosity, which functions as a cam, increasing the tendon's moment arm during its principal action of forearm supination.
Jon Henry; Jeff Feinblatt; Christopher C. Kaeding; James Latshaw; Alan Litsky; Roman Sibel; Julie A. Stephens; Grant L. Jones
Lateral releases of the subscapularis tendon
The technique of arthroscopic subscapularis repair continues to evolve. A three-sided subscapularis release (e.g. anterior, posterior, superior) is commonly advocated for improving tendon excursion to bone. However, a lateral release is commonly required as well, particularly for full thickness, upper subscapularis tears and full thickness, complete subscapularis tears. We describe the techniques to identify and release the lateral subscapularis border, which aids in the completion of other releases. PMID:24403761
Lo, Ian K.Y.; Nelson, Atiba A.; Burkhart, Stephen S
Surgical treatment of partial Achilles tendon rupture
Fifty-four patients with a total of 58 partial ruptures of the Achilles tendon were treated surgically. The postoperative observation time ranged from 8 months to 7 years. Forty-six patients indicated that they were pleased with the results, 8 were satisfied, and 3 were unsatisfied (one died during the interim). Thirty-seven of the 44 patients who had been engaged in competitive
Tor Finn Denstad; Asbj�rn Roaas
Quadriceps Tendon Rupture due to Postepileptic Convulsion
We present a case of quadriceps tendon (QT) rupture. QT ruptures can occur in all ages. The cause is mostly traumatic in origin. Spontaneous ruptures that are thought to result from predisposing conditions are rare. Post-convulsion QT ruptures lacking traumas in their history can be overlooked in clinical examinations. This should be born in mind by the attending physician, as early diagnosis and treatment of the condition can lead to satisfactory outcomes. PMID:24944977
Erkut, Adem; Guvercin, Yilmaz; Sahin, Rifat; Keskin, Davut
Achilles tendon infection due to Mycobacterium chelonae.
Atypical tuberculous tenosynovitis of the foot and ankle is extremely rare. The determination of the Mycobacterium species is essential because resistance of atypical mycobacterial strains to antituberculous drugs is often encountered. We report a case of Mycobacterium chelonae paratendinous and intratendinous infection involving the Achilles tendon. Repeat aggressive irrigation and debridement procedures, coupled with removal of foreign materials and the appropriate use of prolonged antibiotic therapy, can result in a successful long-term outcome. PMID:24529751
Lui, Tun Hing; Chan, Kwok Bill
An Artificial Tendon with Durable Muscle Interface
A coupling mechanism that can permanently fix a forcefully contracting muscle to a bone anchor or any totally inert prosthesis would meet a serious need in orthopaedics. Our group developed the OrthoCoupler� device to satisfy these demands. The objective of this study was to test OrthoCoupler�s performance in vitro and in vivo in the goat semitendinosus tendon model. For in vitro evaluation, 40 samples were fatigue-tested, cycling at 10 load levels, n=4 each. For in vivo evaluation, the semitendinosus tendon was removed bilaterally in 8 goats. Left sides were reattached with an OrthoCoupler, and right sides were reattached using the Krackow stitch with #5 braided polyester sutures. Specimens were harvested 60 days post-surgery and assigned for biomechanics and histology. Fatigue strength of the devices in vitro was several times the contractile force of the semitendinosus muscle. The in vivo devices were built equivalent to two of the in vitro devices, providing an additional safety factor. In strength testing at necropsy, suture controls pulled out at 120.5 � 68.3 N, whereas each OrthoCoupler was still holding after the muscle tore, remotely, at 298�111.3N (mean � SD)(p<0.0003). Muscle tear strength was reached with the fiber-muscle composite produced in healing still soundly intact. This technology may be of value for orthopaedic challenges in oncology, revision arthroplasty, tendon transfer, and sports-injury reconstruction. PMID:19639642
Melvin, Alan; Litsky, Alan; Mayerson, Joel; Witte, David; Melvin, David; Juncosa-Melvin, Natalia
Low level laser therapy in healing tendon
NASA Astrophysics Data System (ADS)
This study aims to verify the effects of AsGa Laser in the scarring of tendon lesion in rats with low nourishment condition and to analyze the ideal light density by means of histopathologic findings highlighted by light microscopy. After the proposed nutritional condition was verified the animals were divided into 3 groups denominated as follows: GI control group, GII laser 1 J/sq.cm. and GIII laser 4 J/sq.cm. The lesions were induced by means of routine surgical process for tendon exposure: There was a crushing process with Allis pincers followed by saturated incision. The data obtained in relation to the amount of macrophage, leukocyte, fibroblast, vessel neoformation, fibrosis and collagen were submitted to parametric statistic procedures of variance analysis and "Tukey" Test and the result obtained was p < 0,05. According to the obtained results it can be concluded that low power laser therapy proved to be efficient in tendon repairing even though the animals suffered from malnutrition as well as the 1 J energy density proved to be more efficient in this case.
Carvalho, P. T. C.; Batista, Cheila O. C.; Fab�ola, C.
Evolutionary transformations of myoseptal tendons in gnathostomes.
Axial undulations in fishes are powered by a series of three-dimensionally folded myomeres separated by sheets of connective tissue, the myosepta. Myosepta have been hypothesized to function as transmitters of muscular forces to axial structures during swimming, but the difficulty of studying these delicate complex structures has precluded a more complete understanding of myoseptal mechanics. We have developed a new combination of techniques for visualizing the three-dimensional morphology of myosepta, and here we present their collagen-fibre architecture based on examination of 62 species representing all of the major clades of notochordates. In all gnathostome fishes, each myoseptum bears a set of six specifically arranged tendons. Because these tendons are not present outside the gnathostomes (i.e. they are absent from lampreys, hagfishes and lancelets), they represent evolutionary novelties of the gnathostome ancestor. This arrangement has remained unchanged throughout 400 Myr of gnathostome evolution, changing only on the transition to land. The high uniformity of myoseptal architecture in gnathostome fishes indicates functional significance and may be a key to understanding general principles of fish swimming mechanics. In the design of future experiments or biomechanical models, myosepta have to be regarded as tendons that can distribute forces in specific directions. PMID:12816635
Gemballa, Sven; Ebmeyer, Leoni; Hagen, Katja; Hannich, Tobias; Hoja, Kathrin; Rolf, Mara; Treiber, Kerstin; Vogel, Felix; Weitbrecht, Gerd
Tendon transfer options in managing the adult flexible flatfoot.
Patients undergoing surgery for posterior tibial tendon dysfunction may require tendon transfer. The flexor digitorum longus is most commonly transferred, although the flexor hallucis longus and peroneus brevis have also been described in the literature. This article discusses the advantages and disadvantages of the different tendons, the surgical techniques used to perform them, and their results in the literature, concentrating principally on studies in which additional bone procedures were not performed. This article will also discuss the potential role for isolated soft tissue procedures in the treatment of stage 2 posterior tibial tendon dysfunction. PMID:22541521
Aronow, Michael S
Prevention of Tendon Adhesions by ERK2 Small Interfering RNAs
Tendon adhesions are one of the most concerning complications after surgical repair of flexor tendon injury. Extracellular signal-regulated kinase (ERK) 2 plays crucial roles in fibroblast proliferation and collagen expression which contributes to the formation of tendon adhesions after flexor tendon surgery. Using a chicken model, we have examined the effects of a small interfering RNA (siRNA) targeting ERK2 delivered by a lentiviral system on tendon adhesion formation with an adhesion scoring system, histological assessment, and biomechanical evaluation. It was found that ERK2 siRNA effectively suppressed the increase of fibroblasts and the formation of tendon adhesions (p < 0.05 compared with the control group). Moreover, no statistically significant reduction in breaking force was detected between the ERK2 siRNA group and the control group. These results show that the lentiviral-mediated siRNA system is effective in preventing tendon adhesion formation but not to tendon healing, and may be used for tendon repair after confirmation and improvement by future detailed studies. PMID:23429276
Ruan, Hongjiang; Liu, Shen; Li, Fengfeng; Li, Xujun; Fan, Cunyi
Biology and augmentation of tendon-bone insertion repair
Surgical reattachment of tendon and bone such as in rotator cuff repair, patellar-patella tendon repair and anterior cruciate ligament (ACL) reconstruction often fails due to the failure of regeneration of the specialized tissue ("enthesis") which connects tendon to bone. Tendon-to-bone healing taking place between inhomogenous tissues is a slow process compared to healing within homogenous tissue, such as tendon to tendon or bone to bone healing. Therefore special attention must be paid to augment tendon to bone insertion (TBI) healing. Apart from surgical fixation, biological and biophysical interventions have been studied aiming at regeneration of TBI healing complex, especially the regeneration of interpositioned fibrocartilage and new bone at the healing junction. This paper described the biology and the factors influencing TBI healing using patella-patellar tendon (PPT) healing and tendon graft to bone tunnel healing in ACL reconstruction as examples. Recent development in the improvement of TBI healing and directions for future studies were also reviewed and discussed. PMID:20727196
Impact of oestrogen deficiency and aging on tendon: concise review
Summary The knowledge about tendons and tenocyte biological behaviour during aging and, especially, oestrogen deficiency is limited. Women differ from men with regard to muscle and tendon, most likely due to differences in sex hormones activity and tissue response. To-date the interest in metabolic factors that may induce tendon disorders is growing. The aim of this paper is to elucidate the current findings in the correlation between oestrogen deficiency, aging and tendon pathology and to encourage future researches to ameliorate assessment and management of tendinopathies in postmenopausal women. PMID:25489550
Frizziero, Antonio; Vittadini, Filippo; Gasparre, Giuseppe; Masiero, Stefano
Background Acute patellar tendon ruptures with poor tissue quality. Ruptures that have been neglected are difficult to repair. Several surgical techniques for the repair of the patellar tendon have been reported, however, these techniques remain difficult because of contractures, adhesions, and atrophy of the quadriceps muscle after surgery. Case presentation We report the cases of 2 Japanese patients (Case 1: a 16-year-old male and Case 2: a 43-year-old male) with patellar tendon ruptures who were treated by reconstruction using semitendinosus-gracilis (STG) tendons with preserved distal insertions. Retaining the original insertion of the STG appears to preserve its viability and provide the revascularization necessary to accelerate healing. Both tendons were placed in front of the patella, in a figure-of-eight fashion, providing stability to the patella. Conclusion Both patients recovered near normal strength and stability of the patellar tendon as well as restoration of function after the operation. PMID:24010848
Habitual loading results in tendon hypertrophy and increased stiffness of the human patellar tendon.
The purpose of this study was to examine patellar tendon (PT) size and mechanical properties in subjects with a side-to-side strength difference of > or =15% due to sport-induced loading. Seven elite fencers and badminton players were included. Cross-sectional area (CSA) of the PT obtained from MRI and ultrasonography-based measurement of tibial and patellar movement together with PT force during isometric contractions were used to estimate mechanical properties of the PT bilaterally. We found that distal tendon and PT, but not mid-tendon, CSA were greater on the lead extremity compared with the nonlead extremity (distal: 139 +/- 11 vs. 116 +/- 7 mm(2); mid-tendon: 85 +/- 5 vs. 77 +/- 3 mm(2); proximal: 106 +/- 7 vs. 83 +/- 4 mm(2); P < 0.05). Distal tendon CSA was greater than proximal and mid-tendon CSA on both the lead and nonlead extremity (P < 0.05). For a given common force, stress was lower on the lead extremity (52.9 +/- 4.8 MPa) compared with the nonlead extremity (66.0 +/- 8.0 MPa; P < 0.05). PT stiffness was also higher in the lead extremity (4,766 +/- 716 N/mm) compared with the nonlead extremity (3,494 +/- 446 N/mm) (P < 0.05), whereas the modulus did not differ (lead 2.27 +/- 0.27 GPa vs. nonlead 2.16 +/- 0.28 GPa) at a common force. These data show that a habitual loading is associated with a significant increase in PT size and mechanical properties. PMID:18556433
Coupp�, C; Kongsgaard, M; Aagaard, P; Hansen, P; Bojsen-Moller, J; Kjaer, M; Magnusson, S P
The flexor digitorum longus, the tendon most often used for transfer in posterior tibial tendon insufficiency, is one-half to one-third the size of the posterior tibial tendon. Occasionally it may be particularly small or may have been previously used for transfer. In these cases, the senior author has felt that the addition of a transfer of the Peroneus Brevis (PBr) tendon may be helpful in maintaining sufficient tendon and muscle mass to rebalance the foot. Thirteen patients who underwent this procedure were retrospectively identified and matched by age and length of follow-up to patients who underwent a more standard tendon transfer operation minus the addition of the PBr transfer. Pain and functional status were then assessed by the American Orthopaedic Foot and Ankle Society's ankle/hindfoot rating scale. Each patient was tested by an independent physical therapist to evaluate inversion and eversion strength. The mean duration of follow-up was 20.6 months (12 to 34 months). The average AOFAS score of the PBr group was 75.8 compared to 71.5 for the standard control group. There was no significant difference between the groups when inversion or eversion strengths were compared. Inversion strength and eversion strength was rated good or excellent (4 or 5) in 12 out of 13 of the PBr transfer group patients. No major complications were encountered in either group. Although it does not increase inversion strength, a PBr transfer can be used to augment a small FDL without causing significant eversion weakness. This can be useful when the FDL is particularly small or in revision surgery. PMID:11354442
Song, S J; Deland, J T
This investigation was to our knowledge the first to use the microdialysis technique to study concentrations of substances\\u000a in a human tendon. In four patients (mean age 40.7 years) with a painful nodule in the Achilles tendon (chronic Achilles tendinosis)\\u000a and in five controls (mean age 37.2 years) with normal Achilles tendons (confirmed by ultrasonography) the local concentrations\\u000a of glutamate
H. Alfredson; K. Thorsen; R. Lorentzon
Repair of Achilles tendon defect with autologous ASCs engineered tendon in a rabbit model.
Adipose derived stem cells (ASCs) are an important cell source for tissue regeneration and have been demonstrated the potential of tenogenic differentiation in vitro. This study explored the feasibility of using ASCs for engineered tendon repair in vivo in a rabbit Achilles tendon model. Total 30 rabbits were involved in this study. A composite tendon scaffold composed of an inner part of polyglycolic acid (PGA) unwoven fibers and an outer part of a net knitted with PGA/PLA (polylactic acid) fibers was used to provide mechanical strength. Autologous ASCs were harvested from nuchal subcutaneous adipose tissues and in vitro expanded. The expanded ASCs were harvested and resuspended in culture medium and evenly seeded onto the scaffold in the experimental group, whereas cell-free scaffolds served as the control group. The constructs of both groups were cultured inside a bioreactor under dynamic stretch for 5 weeks. In each of 30 rabbits, a 2�cm defect was created on right side of Achilles tendon followed by the transplantation of a 3�cm cell-seeded scaffold in the experimental group of 15 rabbits, or by the transplantation of a 3�cm cell-free scaffold in the control group of 15 rabbits. Animals were sacrificed at 12, 21 and 45 weeks post-surgery for gross view, histology, and mechanical analysis. The results showed that short term in vitro culture enabled ASCs to produce matrix on the PGA fibers and the constructs showed tensile strength around 50�MPa in both groups (p�>�0.05). With the increase of implantation time, cell-seeded constructs gradually form neo-tendon and became more mature at 45 weeks with histological structure similar to that of native tendon and with the presence of bipolar pattern and D-periodic structure of formed collagen fibrils. Additionally, both collagen fibril diameters and tensile strength increased continuously with significant difference among different time points (p�<�0.05). In contrast, cell-free constructs failed to form good quality tendon tissue with fibril structure observable only at 45 weeks. There were significant differences in both collagen fibril diameter and tensile strength between two groups at all examined time points (p�<�0.05). The results of this study support that ASCs are likely to be a potential cell source for in vivo tendon engineering and regeneration. PMID:25069604
Deng, Dan; Wang, Wenbo; Wang, Bin; Zhang, Peihua; Zhou, Guangdong; Zhang, Wen Jie; Cao, Yilin; Liu, Wei
Measurement of stress strain and vibrational properties of tendons
NASA Astrophysics Data System (ADS)
The authors present a new non-intrusive experimental procedure based on laser techniques for the measurement of mechanical properties of tendons. The procedure is based on the measurement of the first resonance frequency of the tendon by laser Doppler vibrometry during in vitro tensile experiments, with the final aim of establishing a measurement procedure to perform the mechanical characterization of tendons by extracting parameters such as the resonance frequency, also achievable during in vivo investigation. The experimental procedure is reported, taking into account the need to simulate the physiological conditions of the Achilles tendon, and the measurement technique used for the non-invasive determination of tendon cross-sectional area during tensile vibration tests at different load levels is described. The test procedure is based on a tensile machine, which measures longitudinal tendons undergoing controlled load conditions. Cross-sectional area is measured using a new non-contact procedure for the measurement of tendon perimeter (repeatability of 99% and accuracy of 2%). For each loading condition, vibration resonance frequency and damping, cross-sectional area and tensile force are measured, allowing thus a mechanical characterization of the tendon. Tendon stress-strain curves are reported. Stress-strain curves have been correlated to the first vibration resonance frequency and damping of the tendon measured using a single-point laser Doppler vibrometer. Moreover, experimental results have been compared with a theoretical model of a vibrating cord showing discrepancies. In vitro tests are reported, demonstrating the validity of the method for the comparison of different aged rabbit tendons.
Revel, Gian Marco; Scalise, Alessandro; Scalise, Lorenzo
The development of zebrafish tendon and ligament progenitors.
Despite the importance of tendons and ligaments for transmitting movement and providing stability to the musculoskeletal system, their development is considerably less well understood than that of the tissues they serve to connect. Zebrafish have been widely used to address questions in muscle and skeletal development, yet few studies describe their tendon and ligament tissues. We have analyzed in zebrafish the expression of several genes known to be enriched in mammalian tendons and ligaments, including scleraxis (scx), collagen 1a2 (col1a2) and tenomodulin (tnmd), or in the tendon-like myosepta of the zebrafish (xirp2a). Co-expression studies with muscle and cartilage markers demonstrate the presence of scxa, col1a2 and tnmd at sites between the developing muscle and cartilage, and xirp2a at the myotendinous junctions. We determined that the zebrafish craniofacial tendon and ligament progenitors are neural crest derived, as in mammals. Cranial and fin tendon progenitors can be induced in the absence of differentiated muscle or cartilage, although neighboring muscle and cartilage are required for tendon cell maintenance and organization, respectively. By contrast, myoseptal scxa expression requires muscle for its initiation. Together, these data suggest a conserved role for muscle in tendon development. Based on the similarities in gene expression, morphology, collagen ultrastructural arrangement and developmental regulation with that of mammalian tendons, we conclude that the zebrafish tendon populations are homologous to their force-transmitting counterparts in higher vertebrates. Within this context, the zebrafish model can be used to provide new avenues for studying tendon biology in a vertebrate genetic system. PMID:24803652
Chen, Jessica W; Galloway, Jenna L
Sonography of tears of the distal biceps tendon.
OBJECTIVE. The objective of this study was to describe the sonographic appearance of tears of the distal biceps brachii tendon. CONCLUSION. Sonography can reveal complete and partial tears of the distal biceps tendon, thus providing an alternative technique to MR imaging. PMID:11000169
Miller, T T; Adler, R S
MR Imaging of Disorders of the Achilles Tendon
he Achilles tendon is among the most frequently injured tendons of the body with a variety of types of traumatic and overuse conditions affecting it. These conditions are common, often come to clinical attention, and are frequently imaged. The pathophysiology of Achilles disorders is complex, and the nomenclature is irregularly applied; this leads to miscommunication be- tween clinicians and radiologists
Mark E. Schweitzer; David Karasick
Platelet concentrate injection improves Achilles tendon repair in rats
Background Blood platelets release a cocktail of growth factors when activated, some of which are thought to initi- ate and stimulate repair. Experiment and findings We studied whether a plate- let concentrate injection would improve Achilles tendon repair in an established rat model. The Achilles tendon was transected and a 3 mm segment removed. After 6h, a platelet concentrate was
Per Aspenberg; Olena Virchenko
New finding in the radiographic diagnosis of Achilles tendon rupture
The authors describe a new radiographic sign of rupture of the Achilles tendon system. It is a fracture, with separation through an osteophyte at the insertion of this tendon. Previously reported signs are also discussed as well as the present case report.
Newmark, H.; Mellon, W.S. Jr.; Malhotra, A.K.; Olken, S.M.; Halls, J.
Muscle power attenuation by tendon during energy dissipation.
An important function of skeletal muscle is deceleration via active muscle fascicle lengthening, which dissipates movement energy. The mechanical interplay between muscle contraction and tendon elasticity is critical when muscles produce energy. However, the role of tendon elasticity during muscular energy dissipation remains unknown. We tested the hypothesis that tendon elasticity functions as a mechanical buffer, preventing high (and probably damaging) velocities and powers during active muscle fascicle lengthening. We directly measured lateral gastrocnemius muscle force and length in wild turkeys during controlled landings requiring rapid energy dissipation. Muscle-tendon unit (MTU) strain was measured via video kinematics, independent of muscle fascicle strain (measured via sonomicrometry). We found that rapid MTU lengthening immediately following impact involved little or no muscle fascicle lengthening. Therefore, joint flexion had to be accommodated by tendon stretch. After the early contact period, muscle fascicles lengthened and absorbed energy. This late lengthening occurred after most of the joint flexion, and was thus mainly driven by tendon recoil. Temporary tendon energy storage led to a significant reduction in muscle fascicle lengthening velocity and the rate of energy absorption. We conclude that tendons function as power attenuators that probably protect muscles against damage from rapid and forceful lengthening during energy dissipation. PMID:21957134
Konow, Nicolai; Azizi, Emanuel; Roberts, Thomas J
MAC-EYE: a Tendon Driven Fully Embedded Robot Eye
MAC-EYE: a Tendon Driven Fully Embedded Robot Eye Dario Biamino, Giorgio Cannata, Marco Maggiali the possibility of designing a robot eye with kinematics and actuation similar to those of the human eye. In particular, we tried to exploit the spherical shape of the eye and to study the feasibility of a tendon based
Cannata, Giorgio
Tendon xanthomas as indicators of atherosclerotic burden on coronary arteries
The presence of tendon xanthomas is an almost certain indicator of familial hypercholesterolemia (FH). They also reflect coronary atherosclerotic burden and therefore must be treated aggressively. Tendon xanthomas also occur in two rare conditions, cerebrotendinous xanthomatosis and sitosterolemia, which are not easily confused with FH, can be easily differentiated with clinical history and biochemical tests. PMID:23993019
Patil, Shivanand; Kharge, Jayashree; Bagi, Vittal; Ramalingam, Rangaraj
Achilles tendon biomechanics in response to acute intense exercise.
Achilles tendinopathy is a common disorder and is more prevalent in men. Although differences in tendon mechanics between men and women have been reported, understanding of tendon mechanics in young active people is limited. Moreover, there is limited understanding of changes in tendon mechanics in response to acute exercise. Our purpose was to compare Achilles tendon mechanics in active young adult men and women at rest and after light and strenuous activity in the form of repeated jumping with an added load. Participants consisted of 17 men and 14 women (18-30 years) who were classified as being at least moderately physically active as defined by the International Physical Activity Questionnaire. Tendon force/elongation measures were obtained during an isometric plantarflexion contraction on an isokinetic dynamometer with simultaneous ultrasound imaging of the Achilles tendon approximate to the soleus myotendinous junction. Data were collected at rest, after a 10-minute treadmill walk, and after a fatigue protocol of 100 toe jumps performed in a Smith machine, with a load equaling 20% of body mass. We found greater tendon elongation, decreased stiffness, and lower Young's modulus only in women after the jumping exercise. Force and stress were not different between groups but decreased subsequent to the jumping exercise bout. In general, women had greater elongation and strain, less stiffness, and a lower Young's modulus during plantarflexor contraction. These data demonstrate differences in tendon mechanics between men and women and suggest a potential protective mechanism explaining the lower incidence of Achilles tendinopathy in women. PMID:24552794
Joseph, Michael F; Lillie, Kurtis R; Bergeron, Daniel J; Cota, Kevin C; Yoon, Joseph S; Kraemer, William J; Denegar, Craig R
Transfer bond stresses generated between FRP tendons and concrete
Transfer bond stresses generated between FRP tendons and concrete J. M. Lees�? and C. J. Burgoyne such as fibre-reinforced plastics (FRPs) are lightweight, strong, and, for the most part, non-corrodible. Hence, the use of FRPs as prestressing tendons for concrete represents a viable, durable alternative
Burgoyne, Chris
Review article: Treatment for Achilles tendon ruptures in athletes.
Treatment for Achilles tendon ruptures in athletes is controversial. Surgical fixation has lower rates of re-rupture and confers increased strength and function, whereas conservative treatment has lower risks of wound complications. We review the literature on the optimal treatment for Achilles tendon rupture in athletes. PMID:24014791
Stavrou, Maria; Seraphim, Andreas; Al-Hadithy, Nawfal; Mordecai, Simon C
Fibroma of tendon sheath of the infrapatellar fat pad
We report on a 13-year-old boy who was found to have a fibroma of the tendon sheath associated with the patellar tendon and\\u000a within Hoffa�s fat pad of the knee. This benign tumor has never been described in this location previously. The MRI characteristics\\u000a are correlated with the histologic findings.
John Hur; Timothy A. Damron; Andrei I. Vermont; Sharad C. Mathur
Muscle power attenuation by tendon during energy dissipation
An important function of skeletal muscle is deceleration via active muscle fascicle lengthening, which dissipates movement energy. The mechanical interplay between muscle contraction and tendon elasticity is critical when muscles produce energy. However, the role of tendon elasticity during muscular energy dissipation remains unknown. We tested the hypothesis that tendon elasticity functions as a mechanical buffer, preventing high (and probably damaging) velocities and powers during active muscle fascicle lengthening. We directly measured lateral gastrocnemius muscle force and length in wild turkeys during controlled landings requiring rapid energy dissipation. Muscle-tendon unit (MTU) strain was measured via video kinematics, independent of muscle fascicle strain (measured via sonomicrometry). We found that rapid MTU lengthening immediately following impact involved little or no muscle fascicle lengthening. Therefore, joint flexion had to be accommodated by tendon stretch. After the early contact period, muscle fascicles lengthened and absorbed energy. This late lengthening occurred after most of the joint flexion, and was thus mainly driven by tendon recoil. Temporary tendon energy storage led to a significant reduction in muscle fascicle lengthening velocity and the rate of energy absorption. We conclude that tendons function as power attenuators that probably protect muscles against damage from rapid and forceful lengthening during energy dissipation. PMID:21957134
Konow, Nicolai; Azizi, Emanuel; Roberts, Thomas J.
Force Model for Control of Tendon Driven Hands
NASA Technical Reports Server (NTRS)
Knowing the tendon forces generated for a given task such as grasping via a model, an artificial hand can be controlled. A two-dimensional force model for the index finger was developed. This system is assumed to be in static equilibrium, therefore, the equations of equilibrium were applied at each joint. Constraint equations describing the tendon branch connectivity were used. Gaussian elimination was used to solve for the unknowns of the Linear system. Results from initial work on estimating tendon forces in post-operative hands during active motion therapy were discussed. The results are important for understanding the effects of hand position on tendon tension, elastic effects on tendon tension, and overall functional anatomy of the hand.
Pena, Edward; Thompson, David E.
Specialisation of extracellular matrix for function in tendons and ligaments
Summary Tendons and ligaments are similar structures in terms of their composition, organisation and mechanical properties. The distinction between them stems from their anatomical location; tendons form a link between muscle and bone while ligaments link bones to bones. A range of overlapping functions can be assigned to tendon and ligaments and each structure has specific mechanical properties which appear to be suited for particular in vivo function. The extracellular matrix in tendon and ligament varies in accordance with function, providing appropriate mechanical properties. The most useful framework in which to consider extracellular matrix differences therefore is that of function rather than anatomical location. In this review we discuss what is known about the relationship between functional requirements, structural properties from molecular to gross level, cellular gene expression and matrix turnover. The relevance of this information is considered by reviewing clinical aspects of tendon and ligament repair and reconstructive procedures. PMID:23885341
Birch, Helen L.; Thorpe, Chavaunne T.; Rumian, Adam P.
Surgical treatment of peroneal tendon tears.
The focus of this article is the diagnosis and treatment of peroneal tendon tears. The article first describes mechanisms of injuries resulting in peroneal brevis and longus tears. Associated pathologies, such as ankle instability, hindfoot varus, hypertrophied peroneal tubercle, are discussed. Following sections on diagnosis and conservative treatment, the article describes operative treatment for isolated peroneus brevis tear, isolated peroneus longus tear, and tears of both the peroneus longus and brevis. The authors also discuss hamstring allograft reconstruction, the silicone rod technique, flexor digitorum longus transfer to the peroneus brevis, and treatment of associated pathology. PMID:17996622
Squires, Natalie; Myerson, Mark S; Gamba, Cesar
Summary Tendon lesions are among the most frequent musculoskeletal pathologies. Vascular endothelial growth factor (VEGF) is known to regulate angiogenesis. VEGF-111, a biologically active and proteolysis-resistant splice variant of this family, was recently identified. This study aimed at evaluating whether VEGF-111 could have a therapeutic interest in tendon pathologies. Surgical section of one Achilles tendon of rats was performed before a local injection of either saline or VEGF-111. After 5, 15 and 30 days, the Achilles tendons of 10 rats of both groups were sampled and submitted to a biomechanical tensile test. The force necessary to induce tendon rupture was greater for tendons of the VEGF-111 group (p<0.05) while the section areas of the tendons were similar. The mechanical stress was similar at 5 and 15 days in the both groups but was improved for the VEGF-111 group at day 30 (p <0.001). No difference was observed in the mRNA expression of collagen III, tenomodulin and MMP-9. In conclusion, we observed that a local injection of VEGF-111 improves the early phases of the healing process of rat tendons after a surgical section. Further confirmatory experimentations are needed to consolidate our results. PMID:24932443
Kaux, Jean-Fran�ois; Janssen, Lauriane; Drion, Pierre; Nusgens, Betty; Libertiaux, Vincent; Pascon, Fr�d�ric; Heyeres, Antoine; Hoffmann, Audrey; Lambert, Charles; Le Goff, Caroline; Deno�l, Vincent; Defraigne, Jean-Olivier; Rickert, Markus; Crielaard, Jean-Michel; Colige, Alain
Minimising post-operative donor site morbidity is an important consideration when selecting a graft for surgical reconstruction of the torn anterior cruciate ligament (ACL). One of the most common procedures, the bone-patellar tendon-bone (BPTB) graft involves removal of the central third from the tendon. However, it is unknown whether the mechanical properties of the donor site (patellar tendon) recover. The present study investigated the mechanical properties of the human patellar tendon in 12 males (mean+/-S.D. age: 37+/-14 years) who had undergone surgical reconstruction of the ACL using a BPTB graft between 1 and 10 years before the study (operated knee; OP). The uninjured contralateral knee served as a control (CTRL). Patellar tendon mechanical properties were assessed in vivo combining dynamometry with ultrasound imaging. Patellar tendon stiffness was calculated from the gradient of the tendon's force-elongation curve. Tendon stiffness was normalised to the tendon's dimensions to obtain the tendon's Young's modulus. Cross-sectional area (CSA) of OP patellar tendons was larger by 21% than CTRL tendons (P<0.01). Patellar tendon stiffness was not significantly different between OP and CTRL tendons, but the Young's modulus was lower by 24% in OP tendons (P<0.01). A compensatory enlargement of the patellar tendon CSA, presumably due to scar tissue formation, enabled a recovery of tendon stiffness in the OP tendons. The newly formed tendon tissue had inferior properties as indicated by the reduced tendon Young's modulus, but it increased to a level that enabled recovery of tendon stiffness. PMID:19268289
Reeves, Neil D; Maganaris, Constantinos N; Maffulli, Nicola; Rittweger, Joern
Following tendon tear, the musculo-tendinous unit retracts permanently, looses muscle fibre volume and is infiltrated with fat. This is currently considered to be an unexplained degenerative process. In a sheep model of chronic tendon tear with delayed tendon repair (35 weeks after tendon release), we studied the nature of these muscle changes in eight experimental animals. At sacrifice (75 weeks
Dominik C. Meyer; Hans Hoppeler; Brigitte von Rechenberg; Christian Gerber
Achilles Tendon Length and Medial Gastrocnemius Architecture in Children With Cerebral Palsy
Achilles Tendon Length and Medial Gastrocnemius Architecture in Children With Cerebral Palsy. Methods: Ultrasound was used to measure Achilles tendon length and muscle-tendon architectural parameters and Scheffe post hoc tests. Results: The CP groups had longer Achilles tendons and shorter muscle bellies than
Valero-Cuevas, Francisco
, Stanford, CA (Received 9 September 2002; accepted 18 February 2003) Abstract--The Achilles tendon is one understood. This study examines the ex vivo mechanical behavior of excised human Achilles tendons to elucidate the relationships between mechanical loading and Achilles tendon injury. Eighteen tendons
Stanford University
Tendon-to-bone healing following acute injury is generally poor and often fails to restore normal tendon biomechanical properties. In recent years, the murine patellar tendon (PT) has become an important model system for studying tendon healing and repair due to its genetic tractability and accessible location within the knee. However, the mechanical properties of native murine PT, specifically the regional differences in tissue strains during loading, and the biomechanical outcomes of natural PT-to-bone healing have not been well characterized. Thus, in this study, we analyzed the global biomechanical properties and regional strain patterns of both normal and naturally healing murine PT at three time points (2, 5, and 8 weeks) following acute surgical rupture of the tibial enthesis. Normal murine PT exhibited distinct regional variations in tissue strain, with the insertion region experiencing approximately 2.5 times greater strain than the midsubstance at failure (10.80�2.52% vs. 4.11�1.40%; mean�SEM). Injured tendons showed reduced structural (ultimate load and linear stiffness) and material (ultimate stress and linear modulus) properties compared to both normal and contralateral sham-operated tendons at all healing time points. Injured tendons also displayed increased local strain in the insertion region compared to contralateral shams at both physiologic and failure load levels. 93.3% of injured tendons failed at the tibial insertion, compared to only 60% and 66.7% of normal and sham tendons, respectively. These results indicate that 8 weeks of natural tendon-to-bone healing does not restore normal biomechanical function to the murine PT following injury. PMID:24210849
Gilday, Steven D; Casstevens, E Chris; Kenter, Keith; Shearn, Jason T; Butler, David L
Quantification of regional blood flow to canine flexor tendons
Although the blood supply and the microcirculation of flexor tendons have been studied and defined extensively using qualitative methods, the quantitative assessment of blood flow has been lacking because of the limitations of the available experimental techniques. The authors studied the regional blood supply to the flexor tendons of dogs by the technique of radionuclide-labeled microspheres. Seven adult mongrel dogs were used. Microsphere injection and tissue-counting techniques previously used for other tissues were applied. Samples of proximal, isthmus, and distal portions of the profundus and superficialis flexor tendons were harvested from each digital unit of available limbs from each dog. Mean (+/- SE) flows (ml/100 g dry tissue/min) were proximal profundus 1.78 +/- 0.60 and superficialis 7.10 +/- 1.50. The differences were significant. The study suggests that regional variation in blood flow to canine digital flexor tendons exists, so that a single value for blood flow to these tendons is not relevant. Furthermore, the study supports the concept of dual (vascular and synovial) nutrition to the digital flexor tendons in dogs. These observations may have implications regarding tendon repair techniques.
Weidman, K.A.; Simonet, W.T.; Wood, M.B.; Cooney, W.P.; Ilstrup, D.M.
Sutured tendon repair; a multi-scale finite element model.
Following rupture, tendons are sutured to reapproximate the severed ends and permit healing. Several repair techniques are employed clinically, with recent focus towards high-strength sutures, permitting early active mobilisation thus improving resultant joint mobility. However, the arrangement of suture repairs locally alters the loading environment experienced by the tendon. The extent of the augmented stress distribution and its effect on the tissue is unknown. Stress distribution cannot be established using traditional tensile testing, in vivo, or ex vivo study of suture repairs. We have developed a 3D finite element model of a Kessler suture repair employing multiscale modelling to represent tendon microstructure and incorporate its highly orthotropic behaviour into the tissue description. This was informed by ex vivo tensile testing of porcine flexor digitorum profundus tendon. The transverse modulus of the tendon was 0.2551 [Formula: see text] 0.0818�MPa and 0.1035 [Formula: see text] 0.0454�MPa in proximal and distal tendon samples, respectively, and the interfibrillar tissue modulus ranged from 0.1021 to 0.0416�MPa. We observed an elliptically shaped region of high stress around the suture anchor, consistent with a known region of acellularity which develop 72�h post-operatively and remain for at least a year. We also observed a stress shielded region close to the severed tendon ends, which may impair collagen fibre realignment during the remodelling stage of repair due to the lack of tensile stress. PMID:24840732
Rawson, Shelley D; Margetts, Lee; Wong, Jason K F; Cartmell, Sarah H
Current Concepts in Examination and Treatment of Elbow Tendon Injury
Context: Injuries to the tendons of the elbow occur frequently in the overhead athlete, creating a significant loss of function and dilemma to sports medicine professionals. A detailed review of the anatomy, etiology, and pathophysiology of tendon injury coupled with comprehensive evaluation and treatment information is needed for clinicians to optimally design treatment programs for rehabilitation and prevention. Evidence Acquisitions: The PubMed database was searched in January 2012 for English-language articles pertaining to elbow tendon injury. Results: Detailed information on tendon pathophysiology was found along with incidence of elbow injury in overhead athletes. Several evidence-based reviews were identified, providing a thorough review of the recommended rehabilitation for elbow tendon injury. Conclusions: Humeral epicondylitis is an extra-articular tendon injury that is common in athletes subjected to repetitive upper extremity loading. Research is limited on the identification of treatment modalities that can reduce pain and restore function to the elbow. Eccentric exercise has been studied in several investigations and, when coupled with a complete upper extremity strengthening program, can produce positive results in patients with elbow tendon injury. Further research is needed in high-level study to delineate optimal treatment methods. PMID:24427389
Ellenbecker, Todd S.; Nirschl, Robert; Renstrom, Per
Production of a sterilised decellularised tendon allograft for clinical use.
Application of a high-level decontamination or sterilisation procedure and cell removal technique to tendon allograft can reduce the concerns of disease transmission, immune reaction, and may improve remodelling of the graft after implantation. The decellularised matrix can also be used as a matrix for tendon tissue engineering. One such sterilisation factor, Peracetic acid (PAA) has the advantage of not producing harmful reaction residues. The aim of this study was to evaluate the effects of PAA treatment and a cell removal procedure on the production of tendon matrix. Human patellar tendons, thawed from frozen were treated respectively as: Group 1, control with no treatment; Group 2, sterilised with PAA (0.1�% (w/v) PAA for 3�h) Group 3, decellularised (incubation successively in hypotonic buffer, 0.1�% (w/v) sodium dodecyl sulphate, and a nuclease solution); Group 4, decellularised and PAA sterilised. Histological analysis showed that no cells were visible after the decellularisation treatment. The integrity of tendon structure was maintained after decellularisation and PAA sterilisation, however, the collagen waveform was slightly loosened. No contact cytotoxicity was found in any of the groups. Determination of de-natured collagen showed no significant increase when compared with the control. This suggested that the decellularisation and sterilisation processing procedures did not compromise the major properties of the tendon. The sterilised, decellularised tendon could be suitable for clinical use. PMID:23443409
Huang, Q; Ingham, E; Rooney, P; Kearney, J N
The "turtleneck" pulley plasty for finger flexor tendon repair.
Injuries to the flexor tendons are frequent. Even when correctly treated, they can cause a loss of mobility of the digits secondary to postoperative adhesions. Further, conflicts between the tendon suture and the pulleys can limit the range of motion of the tendon and the flexion of the fingers. We propose a new pulley plasty that permits immediate retraining and avoids conflict with the tendon suture. Ten patients underwent surgery for a tendon injury in zone II, with no lesions of the associated pedicles. The tendons were repaired by a 4-strand stitch technique associated with a continuous peritendinous suture. Pulley plasty was systematically performed on A2, A4, or both. Eight patients recovered a satisfactory range of motion with a finger to palm distance of <1 cm, and 2 others with a distance of <2 cm. Two tenolyses were performed, for which no secondary reconstruction of the pulleys was necessary. This plasty technique is simple to carry out, reliable, and reproducible. Because it facilitates tendon repair and reinforces the existing pulleys, it permits immediate retraining and controlled active mobilization. PMID:24275761
Goubier, Jean-Noel; Lafosse, Thibault; Teboul, Fr�d�ric
Preferential tendon stem cell response to growth factor supplementation.
Tendon injuries are increasingly prevalent around the world, accounting for more than 100 000 new clinical cases/year in the USA alone. Cell-based therapies have been proposed as a therapeutic strategy, with recent data advocating the use of tendon stem cells (TSCs) as a potential cell source with clinical relevance for tendon regeneration. However, their in vitro expansion is problematic, as they lose their multipotency and change their protein expression profile in culture. Herein, we ventured to assess the influence of insulin-like growth factor 1 (IGF-1), growth and differentiation factor-5 (GDF-5) and transforming growth factor-?1 (TGF?1) supplementation in TSC culture. IGF-1 preserved multipotency for up to 28?days. Upregulation of decorin and scleraxis expression was observed as compared to freshly isolated cells. GDF-5 treated cells exhibited reduced differentiation along adipogenic and chondrogenic pathways after 28?days, and decorin, scleraxis and collagen type I expression was increased. After 28?days, TGF?1 supplementation led to increased scleraxis, osteonectin and collagen type II expression. The varied responses to each growth factor may reflect their role in tendon repair, suggesting that: GDF-5 promotes the transition of tendon stem cells towards tenocytes; TGF?1 induces differentiation along several pathways, including a phenotype indicative of fibrocartilage or calcified tendon, common problems in tendon healing; and IGF-1 promotes proliferation and maintenance of TSC phenotypes, thereby creating a population sufficient to have a beneficial effect. Copyright � 2014 John Wiley & Sons, Ltd. PMID:24474722
Holladay, Carolyn; Abbah, Sunny-Akogwu; O'Dowd, Colm; Pandit, Abhay; Zeugolis, Dimitrios I
Conflicts, snapping and instability of the tendons. Pictorial essay
Conflicts, snapping and instability of the tendons are common, and ultrasound (US) is the method of choice for evidencing these conditions thanks to the possibility to perform dynamic maneuvers during imaging studies. A conflict can occur between a tendon and a bone structure, other tendons, the retinacula or pulleys. Snapping can occur due to instability caused by rupture of the retinaculum, conflict between a thickened retinaculum and a bone prominence or due to an abnormal position of the tendon. Instability can occur due to insufficient ability of the retinaculum to keep the tendons in the bone groove or its failure to hold the tendons applied to the bone. The technique for evidencing conflicts, snapping and instability of the tendons is very demanding because it requires a thorough knowledge of the US appearance and dynamic maneuvers. However, at the present time US examination completed with dynamic maneuvers is the investigation of choice for evidencing these disorders and providing the clinicians with the necessary information. PMID:23396604
Fantino, Olivier; Borne, J.; Bordet, Bertrand
For a variety of reasons, bone�patellar tendon�bone and Achilles tendon allografts have been used more commonly in anterior cruciate ligament reconstruction. Soft-tissue allografts used mainly are the semitendinosus, gracilis, and occasionally the quadriceps tendons. The anterior tibialis tendon is a thick, strong tendon that can be prepared with one doubling of the graft, has a large cross-sectional area, and has
David N. M. Caborn; Jeffrey B. Selby
Tendon xanthomas are a component of familial hypercholesterolaemia, which is a hereditary disease and characterised by elevated low-density lipo protein cholesterol plasma levels and premature coronary artery disease. Tendon xanthomas are diagnostic for heterozygous familial hypercholesterolaemia (HFH) and they mostly occur in Achilles tendon. Sonography and MRI are superior to clinical assessment and are useful in detecting tendon xanthomas. In this report, we present ultrasonographic and MRI findings of multiple tendon xanthomas in a case of HFH. PMID:24252837
Dagistan, Emine; Canan, Arzu; Kizildag, Betul; Barut, Abdullah Yuksel
Imaging horse tendons using multimodal 2-photon microscopy.
Injuries and damage to tendons plague both human and equine athletes. At the site of injuries, various cells congregate to repair and re-structure the collagen. Treatments for collagen injury range from simple procedures such as icing and pharmaceutical treatments to more complex surgeries and the implantation of stem cells. Regardless of the treatment, the level of mechanical stimulation incurred by the recovering tendon is crucial. However, for a given tendon injury, it is not known precisely how much of a load should be applied for an effective recovery. Both too much and too little loading of the tendon could be detrimental during recovery. A mapping of the complex local environment imparted to any cell present at the site of a tendon injury may however, convey fundamental insights related to their decision making as a function of applied load. Therefore, fundamentally knowing how cells translate mechanical cues from their external environment into signals regulating their functions during repair is crucial to more effectively treat these types of injuries. In this paper, we studied systems of tendons with a variety of 2-photon-based imaging techniques to examine the local mechanical environment of cells in both normal and injured tendons. These tendons were chemically treated to instigate various extents of injury and in some cases, were injected with stem cells. The results related by each imaging technique distinguish with high contrast and resolution multiple morphologies of the cells' nuclei and the alignment of the collagen during injury. The incorporation of 2-photon FLIM into this study probed new features in the local environment of the nuclei that were not apparent with steady-state imaging. Overall, this paper focuses on horse tendon injury pattern and analysis with different 2-photon confocal modalities useful for wide variety of application in damaged tissues. PMID:23871762
Sivaguru, Mayandi; Eichorst, John Paul; Durgam, Sushmitha; Fried, Glenn A; Stewart, Allison A; Stewart, Matthew C
Triceps tendon tear in a middle-aged weightlifter.
The patient was a 47-year-old man who was evaluated by a physical therapist for a chief complaint of posterior right elbow pain. The patient routinely participated in weightlifting activities and reported a sudden onset of triceps weakness and posterior elbow pain while performing clap push-ups 3 days prior. A physician assistant ordered radiographs, which were initially interpreted as normal, and routine magnetic resonance imaging for the right elbow. Following examination by a physical therapist, due to concern for a triceps tendon tear, the previously ordered magnetic resonance imaging was expedited, which revealed a partial triceps tendon tear with partial tendon retraction medially. PMID:24175622
Molloy, Joseph M; Aberle, Curtis J; Escobar, Eduardo
Surgical treatment options for patella tendon rupture, part II: chronic.
Patella tendon rupture is a debilitating injury that often occurs in the setting of preexisting tendon degeneration. Prompt diagnosis and treatment is essential to prevent retraction of the patella with subsequent adhesions and quadriceps contractures. In the setting of a chronic rupture, augmentation with hamstring tendons or allograft reconstruction generally is necessary. Patients who undergo delayed repair are at risk for a compromised result secondary to loss of full knee flexion and decreased quadriceps strength, although a functional extensor mechanism is likely to be reestablished. Overall the results of chronic repair are less satisfactory than the acute repair, but still provide an extensor mechanism for the patient and thus provide function. PMID:16119741
Greis, Patrick E; Lahav, Amit; Holmstrom, Michael C
Arthroscopic Recognition and Repair of the Torn Subscapularis Tendon
Although the subscapularis has historically received less attention than posterosuperior rotator cuff tears, repair of a torn subscapularis tendon is critically important to restoring anatomy and achieving the best functional outcome possible. Arthroscopic repair begins with proper recognition of the tear. A systematic approach can then be used to arthroscopically repair all types of subscapularis tendon tears, from partial tears to full-thickness tears, as well as those which are retracted and have adhesions medially. Subscapularis footprint restoration can be accomplished with a variety of repair techniques that must be matched to the extent of the tear and mobility of the tendon. PMID:24400185
Denard, Patrick J.; Burkhart, Stephen S.
Acute and chronic Achilles tendon ruptures in athletes.
The Achilles tendon is the most injured tendon of athletes in the lower extremities and is the most common tendon to rupture spontaneously. Operative repair provides earlier return to sporting activities and lesser rate of rerupture. The general goal is to attempt anastomosis of the acute ruptured ends; however, delayed ruptures may require more extensive procedures. New surgical approaches, including percutaneous and mini-open techniques, are being introduced to potentially diminish perioperative complications. Advent of early protective range of motion and rehabilitation has shown a potential for earlier return to sporting activities for Achilles ruptures. PMID:21276522
Thompson, Jonathan; Baravarian, Bob
The long head of the biceps tendon is a suitable cell source for tendon tissue regeneration
Introduction Tendon tissue engineering (TTE) tries to produce tendinous tissue of high quality to replace dysfunctional tissue. One possible application of TTE might be the replacement of ruptured tissue of the rotator cuff. Autologous tenocytes seem to be most suitable as no differentiation in vitro is necessary. Today it is still uncertain if there is a difference between tendon-derived cells (TDC) of different native tissues. Moreover, the search for suitable scaffolds is another important issue in TTE. Material and methods This study compared TDC of the long head of the biceps tendon (LHB), the anterior cruciate ligament (ACL) and the tendon of the musculus semitendinosus (TMS). The TDC were isolated using the cell migration method. Cell morphology was assessed using light microscopy and gene expression was performed using polymerase chain reaction (PCR). Afterwards, cell seeding efficiency and proliferation were tested on a collagen I scaffold using the WST-1 assay. Results were confirmed using H + E staining. Results The TDC of the LHB showed higher expression levels of collagen type I and decorin (p < 0.01) compared to TDC of other origin. Results showed efficient cell seeding and proliferation within the scaffold. Proliferation within the scaffold was not as high as when cells were cultivated without a scaffold. Conclusions The TDC of the LHB seems to be the most suitable cell source. Further research is necessary to find out if the results can be transferred to an in vivo model. The new collagen I scaffold seems to offer an opportunity to combine good biocompatibility and mechanical strength. PMID:25097592
Pietschmann, Matthias F.; G�lecy�z, Mehmet F.; Ficklscherer, Andreas; Jansson, Volkmar; M�ller, Peter E.
Induced pluripotent stem cells (iPSCs) hold great potential for cell therapy and tissue engineering. Neural crest stem cells (NCSCs) are multipotent that are capable of differentiating into mesenchymal lineages. In this study, we investigated whether iPSC-derived NCSCs (iPSC-NCSCs) have potential for tendon repair. Human iPSC-NCSCs were suspended in fibrin gel and transplanted into a rat patellar tendon window defect. At 4 weeks post-transplantation, macroscopical observation showed that the repair of iPSC-NCSC-treated tendons was superior to that of non-iPSC-NCSC-treated tendons. Histological and mechanical examinations revealed that iPSC-NCSCs treatment significantly enhanced tendon healing as indicated by the improvement in matrix synthesis and mechanical properties. Furthermore, transplanted iPSC-NCSCs produced fetal tendon-related matrix proteins, stem cell recruitment factors, and tenogenic differentiation factors, and accelerated the host endogenous repair process. This study demonstrates a potential strategy of employing iPSC-derived NCSCs for tendon tissue engineering. PMID:23815150
Xu, Wei; Wang, Yequan; Liu, Erfu; Sun, Yanjun; Luo, Ziwei; Xu, Zhiling; Liu, Wanqian; Zhong, Li; Lv, Yonggang; Wang, Aijun; Tang, Zhenyu; Li, Song
Flexor tendon injuries are often encountered clinically and typically require surgical repair. Return of function after repair is limited due to adhesion formation, which leads to reduced tendon gliding, and due to a lack of repair site strength, which leads to repair site gap formation or rupture. The application of the growth factors basic fibroblastic growth factor (bFGF) and platelet derived growth factor BB (PDGF-BB) has been shown to have the potential to enhance tendon healing. The objectives of this study were to examine: (1) the conditions over which delivery of bFGF can be controlled from a heparin-binding delivery system (HBDS) and (2) the effect of bFGF and PDGF-BB released from this system on tendon fibroblast proliferation and matrix gene expression in vitro over a 10-day interval. Delivery of bFGF was controlled using a HBDS. Fibrin matrices containing the HBDS retained bFGF better than did matrices lacking the delivery system over the 10-day period studied. Delivery of bFGF and PDGF-BB using the HBDS stimulated tendon fibroblast proliferation and promoted changes in the expression of matrix genes related to tendon gliding, strength, and remodeling. Both growth factors may be effective in enhancing tendon healing in vivo. PMID:19937274
Thomopoulos, Stavros; Das, Rosalina; Sakiyama-Elbert, Shelly; Silva, Matthew J.; Charlton, Nichole; Gelberman, Richard H.
Inuence of bone mineral density, age, and strain rate on the failure mode of human Achilles tendons
Achilles tendons fail. Design. Dual-energy X-ray absorptiometry and mechanical testing of excised Achilles tendon-calcaneus specimens. Background. The Achilles tendon can fail by tendon rupture or bony avulsion treatments selected. Methods. Excised human Achilles tendons were loaded to failure at strain rates of 1% s�?1
Stanford University
Minimally invasive surgery for Achilles tendon pathologies
Minimally invasive trauma and orthopedic surgery is increasingly common, though technically demanding. Its use for pathologies of the Achilles tendon (AT) hold the promise to allow faster recovery times, shorter hospital stays, and improved functional outcomes when compared to traditional open procedures, which can lead to difficulty with wound healing because of the tenuous blood supply and increased chance of wound breakdown and infection. We present the recent advances in the field of minimally invasive AT surgery for tendinopathy, acute ruptures, chronic tears, and chronic avulsions of the AT. In our hands, minimally invasive surgery has provided similar results to those obtained with open surgery, with decreased perioperative morbidity, decreased duration of hospital stay, and reduced costs. So far, the studies on minimally invasive orthopedic techniques are of moderate scientific quality with short follow-up periods. Multicenter studies with longer follow-up are needed to justify the long-term advantages of these techniques over traditional ones. PMID:24198547
Maffulli, Nicola; Longo, Umile Giuseppe; Spiezia, Filippo; Denaro, Vincenzo
Stage IV posterior tibial tendon rupture.
Adult acquired flatfoot deformity progresses through well defined stages as set out by Johnson and Strom. Myerson modified this classification system with the addition of a fourth, more advanced stage of the disease. This stage describes the involvement of the tibiotalar joint in addition to the hindfoot malalignment seen in stages II and III. This most advanced stage is comprised of a hindfoot valgus deformity, resulting from degeneration of the posterior tibial tendon, with associated valgus tilting of the talus within the mortise. The deformity at the tibiotalar joint may or may not be rigid. Although rigid deformities are still best treated with fusions of the ankle and hindfoot, supple tibiotalar deformity may be treated with joint sparing procedures involving reconstructive procedures of the foot and deltoid ligaments. PMID:17561206
Bluman, Eric M; Myerson, Mark S
Cushing, acromegaly, GH deficiency and tendons
Summary Cushing�s syndrome, induced by an endogenous or exogenous cortisol excess, and acromegaly, the clinical syndrome caused by growth hormone (GH) excess in adulthood, as well as the disease induced by GH deficiency (GHD), represent perfect models for the evaluation of the effects induced by chronic exposure in vivo, respectively, to cortisol and GH/IGF-1 excess or deficiency on the complex structure of the tendons as well as on the related post-traumatic repair mechanism. Although the literature is still scant, here in main scientific evidence on this topic is summarized in order to provide suggestions about the management of the above mentioned illnesses, to translate such information in the field of sports medicine and/or traumatology, and to increase and to disseminate knowledge on this misunderstood theme. PMID:25489551
Galdiero, Mariano; Auriemma, Renata S.; Pivonello, Rosario; Colao, Annamaria
Rehabilitating Psoas Tendonitis: A Case Report
This case report describes the examination and physical therapy intervention for a woman with anterior hip pain whose medical diagnosis following magnetic resonance imaging (MRI) was bilateral labral tears and psoas tendinitis. Her physical therapy evaluation revealed findings consistent with psoas tendonitis. Utilizing theories of neuromuscular patterning and knowledge of normal muscle function, the patient was successfully treated in physical therapy following six physical therapy sessions, once a week for 6�weeks. The patient was found to have an overactive psoas muscle, as indicated by hip flexion being the primary mover in her movement patterns, and dysfunctional abdominal and pelvic floor muscles. Functionally based therapeutic exercise and electrical stimulation were used to reeducate the muscles of the abdomen, pelvic floor, and hips in order to create muscular balance and correct muscle dysfunction. PMID:19048347
Fibroma of tendon sheath located within Kager's triangle.
The formation of a fibroma of the tendon sheath, a rare, slow-growing, benign tumor, usually occurs in the upper extremities of young adult males. We present an extremely rare case of a fibroma of the tendon sheath arising adjacent to the Achilles tendon within Kager's triangle in a 41-year-old female. The patient presented with progressive pain localized to the posterior aspect of the left ankle. Complete excision and histopathologic analysis of the fibroma were performed. The patient experienced an uneventful recovery after the intervention and had no evidence of recurrence after 3 months of follow-up. Fibroma of the tendon sheath should be included in the differential diagnosis when a patient presents with a painful soft tissue mass in Kager's triangle. PMID:24556488
Jacobs, Eva; Witlox, Marianne A; Hermus, Joris P S
Surgical treatment of partial biceps tendon ruptures at the elbow.
We present the treatment and results of a consecutive series of 7 patients (mean age, 42.7 years) with partial ruptures of the distal biceps tendon. All injuries occurred as the result of either heavy labor or weightlifting. Diagnosis in all cases was made with magnetic resonance imaging. After failure of conservative therapy, the patients were treated with repair of the distal biceps tendon. Mean follow-up was 30.6 months (range, 25-39 months). Results were uniformly good, with all patients satisfied with the outcome. All patients maintained their preoperative range of motion, with none reporting significant postoperative pain. The only complication was transient neurapraxias of the lateral antebrachial cutaneous nerve in 2 cases. We conclude that patients presenting with chronic pain in the cubital fossa should be evaluated for possible partial biceps tendon tear. If the diagnosis of partial tendon tear is made, surgical repair is a safe and effective method of treatment. PMID:16517368
Dellaero, David T; Mallon, William J
Isolation and growth characteristics of adult human tendon fibroblasts.
An explant method for the isolation of fibroblasts from adult human tendon is described. Cells were successfully isolated from 22 out of 27 common biceps tendons obtained from cadaveric donors (age range 11-83 years). The fibroblasts could be maintained in culture using standard methods and morphologically resembled those of synovial rather than dermal origin. Growth characteristics of 12 cell lines were assessed by deoxyribose nucleic acid (DNA) synthesis using [3H]thymidine incorporation in response to stimulation by fetal calf serum. Cells obtained separately from superficial and deep parts of the tendons produced almost identical responses. No significant reduction in growth response with increasing age was found when related to the age of the donor. Therefore this study did not show any age related defect in the short term tendon fibroblast replicative responses to serum. Images PMID:3592800
Chard, M D; Wright, J K; Hazleman, B L
A model of muscle-tendon function in human walking
In order to motivate the design of legged machines that walk as humans do, this thesis investigates how leg muscles and tendons work mechanically during level-ground human walking at self-selected speeds. I hypothesize ...
Endo, Ken, Ph. D. Massachusetts Institute of Technology
Exploring the role of hypercholesterolemia in tendon health and repair
Summary High cholesterol remains a significant healthcare problem, as more than 13% of adults in the U.S. are affected by hypercholesterolemia. The detrimental effects the disease has on cardiovascular health are well-documented, but the effects on the musculoskeletal system, and more specifically on tendons, have not been thoroughly examined. This paper provides an overview of work performed in our lab with various animal models to elucidate the relationship between high cholesterol and tendon biomechanical integrity and ability to heal. These studies highlight the complexity of relationships between multiple factors that influence tendon biomechanics, and it has offered a better understanding of the implications of high cholesterol on healthy and healing tendons. PMID:25489542
Hast, Michael W.; Abboud, Joseph A.; Soslowsky, Louis J.
Cellular therapy in bone-tendon interface regeneration
The intrasynovial bone-tendon interface is a gradual transition from soft tissue to bone, with two intervening zones of uncalcified and calcified fibrocartilage. Following injury, the native anatomy is not restored, resulting in inferior mechanical properties and an increased risk of re-injury. Recent in vivo studies provide evidence of improved healing when surgical repair of the bone-tendon interface is augmented with cells capable of undergoing chondrogenesis. In particular, cellular therapy in bone-tendon healing can promote fibrocartilage formation and associated improvements in mechanical properties. Despite these promising results in animal models, cellular therapy in human patients remains largely unexplored. This review highlights the development and structure-function relationship of normal bone-tendon insertions. The natural healing response to injury is discussed, with subsequent review of recent research on cellular approaches for improved healing. Finally, opportunities for translating in vivo findings into clinical practice are identified. PMID:24326955
Rothrauff, Benjamin B; Tuan, Rocky S
ultrasound echo intensities. We demonstrate our method on tendinopathy regions in human Achilles tendons or the exterior region of normal tissue. After objectively bounding the tendinopathy, PES segments and tracks
Sethares, William A.
Mechanical properties of the patellar tendon in adults and children.
It is not currently known how the mechanical properties of human tendons change with maturation in the two sexes. To address this, the stiffness and Young's modulus of the patellar tendon were measured in men, women, boys and girls (each group, n=10). Patellar tendon force (F(pt)) was calculated from the measured joint moment during a ramped voluntary isometric knee extension contraction, the antagonist knee extensor muscle co-activation quantified from its electromyographical activity, and the patellar tendon moment arm measured from magnetic resonance images. Tendon elongation was imaged using the sagittal-plane ultrasound scans throughout the contraction. Tendon cross-sectional area was measured at rest from ultrasound scans in the transverse plane. Maximal F(pt) and tendon elongation were (mean+/-SE) 5453+/-307 N and 5+/-0.5 mm for men, 3877+/-307 N and 4.9+/-0.6 mm for women, 2017+/-170 N and 6.2+/-0.5 mm for boys and 2169+/-182 N and 5.9+/-0.7 mm for girls. In all groups, tendon stiffness and Young's modulus were examined at the level that corresponded to the maximal 30% of the weakest participant's F(pt) and stress, respectively; these were 925-1321 N and 11.5-16.5 MPa, respectively. Stiffness was 94% greater in men than boys and 84% greater in women than girls (p<0.01), with no differences between men and women, or boys and girls (men 1076+/-87 N/mm; women 1030+/-139 N/mm; boys 555+/-71 N/mm and girls 561.5+/-57.4 N/mm). Young's modulus was 99% greater in men than boys (p<0.01), and 66% greater in women than girls (p<0.05). There were no differences in modulus between men and women, or boys and girls (men 597+/-49 MPa; women 549+/-70 MPa; boys 255+/-42 MPa and girls 302+/-33 MPa). These findings indicate that the mechanical stiffness of tendon increases with maturation due to an increased Young's modulus and, in females due to a greater increase in tendon cross-sectional area than tendon length. PMID:20045111
O'Brien, Thomas D; Reeves, Neil D; Baltzopoulos, Vasilios; Jones, David A; Maganaris, Constantinos N
A Simple Grafting Method to Repair Irreparable Distal Biceps Tendon
Irreparable distal biceps tendon tears typically are treated using a free tendon graft. We asked whether our new method to\\u000a fix the graft�using two suture anchors�yields similar results to our previous bone canal method. We compared the two methods\\u000a for strength, endurance, and clinical findings. There were two groups, the suture anchor group (Group A, seven patients) and\\u000a the bone
Martti Vastam�ki; Heidi Vastam�ki
Direct Repair without Augmentation of Patellar Tendon Avulsion following TKA
Complications involving the extensor mechanism after TKA are potentially disastrous. We are reporting a case of patellar tendon rupture from tibial tuberosity following total knee arthroplasty. We managed it by direct repair with fiberwire using Krackow suture technique without augmentation. Our long term result has been very encouraging. Our method is a safe and better method of management of patellar tendon avulsion following TKA when it happens without any tissue loss.
Kumar, Nishikant; Yadav, Chandrashekhar; Kumar, Ashok
Individual muscle contributions to the in vivo achilles tendon force
Objective. To ascertain the possibility of non-uniform stress within the achilles tendon due to individual force contributions of the triceps surae.Design. Calculation of non-uniform stress through discrepancies in moments about the ankle joint. Background. Non-uniform stress over the cross-sectional area have been implied in the etiology of achilles tendon injury and may influence functional aspects. However, this has not been
A. N. Arndt; P. V. Komi; G.-P. Br�ggemann; J. Lukkariniemi
Strain and elongation of the human semitendinosus muscle - tendon unit.
The semitendinosus (ST) consists of a long distal tendon and it is divided in two parts by a tendinous inscription (TI). The purpose of this study was to quantify strain and elongation of the TI and the distal tendon of ST. Fourteen subjects performed ramp isometric contractions of the knee flexors at 0�, 45� and 90� of knee flexion. Two ultrasound probes were used to visualize the displacement of the distal tendon and selected points across the TI and aponeuroses. Three-way analysis of variance designs indicated that: (a) strain and elongation of the ST distal muscle-tendon junction were higher than that of the aponeurosis - TI junction points (p < 0.05) (b) the long arm of the TI reach strain of 49.86 � 7.77% which was significantly (p < 0.05) higher than that displayed by the short arm (28.35 � 0.59%) (c) Strain of tendinous and TI-aponeuroses segments significantly increased from 90� to 0� of knee flexion while the inverse was observed for the TI arm length (p < 0.05). (d) Tendon strain was significantly higher than strain of the TI-aponeuroses segments at 45� and 90� of knee flexion while the opposite was observed at 0� of knee flexion. The arrangement of TI along ST length results in differential local strains, indicating that the mechanical properties of the ST muscle are affected by tendon, aponeuroses and tendinous inscription interactions. PMID:23992632
Kellis, Eleftherios; Patsika, Glykeria; Karagiannidis, Evaggelos
Biomimetic scaffold design for functional and integrative tendon repair.
Rotator cuff tears represent the most common shoulder injuries in the United States. The debilitating effect of this degenerative condition coupled with the high incidence of failure associated with existing graft choices underscores the clinical need for alternative grafting solutions. The 2 critical design criteria for the ideal tendon graft would require the graft to not only exhibit physiologically relevant mechanical properties but also be able to facilitate functional graft integration by promoting the regeneration of the native tendon-to-bone interface. Centered on these design goals, this review will highlight current approaches to functional and integrative tendon repair. In particular, the application of biomimetic design principles through the use of nanofiber- and nanocomposite-based scaffolds for tendon tissue engineering will be discussed. This review will begin with nanofiber-based approaches to functional tendon repair, followed by a section highlighting the exciting research on tendon-to-bone interface regeneration, with an emphasis on implementation of strategic biomimicry in nanofiber scaffold design and the concomitant formation of graded multi-tissue systems for integrative soft-tissue repair. This review will conclude with a summary and discussion of future directions. PMID:22244070
Zhang, Xinzhi; Bogdanowicz, Danielle; Erisken, Cevat; Lee, Nancy M; Lu, Helen H
Biomimetic Scaffold Design for Functional and Integrative Tendon Repair
Rotator cuff tears represent the most common shoulder injuries in the United States. The debilitating effect of this degenerative condition coupled with the high incidence of failure associated with existing graft choices underscore the clinical need for alternative grafting solutions. The two critical design criteria for the ideal tendon graft would require the graft to not only exhibit physiologically relevant mechanical properties but also be able to facilitate functional graft integration by promoting the regeneration of the native tendon-to-bone interface. Centered on these design goals, this review will highlight current approaches to functional and integrative tendon repair. In particular, the application of biomimetic design principles through the use of nanofiber- and nanocomposite-based scaffolds for tendon tissue engineering will be discussed. This review will begin with nanofiber-based approaches to functional tendon repair, followed by a section highlighting the exciting research on tendon-to-bone interface regeneration, with an emphasis on implementation of strategic biomimicry in nanofiber scaffold design and the concomitant formation of graded multi-tissue systems for integrative soft tissue repair. This review will conclude with a summary and future directions section. PMID:22244070
Zhang, Xinzhi; Bogdanowicz, Danielle; Erisken, Cevat; Lee, Nancy M.; Lu, Helen H.
Tendon Tissue Engineering: Progress, Challenges, and Translation to the Clinic
The tissue engineering field has made great strides in understanding how different aspects of tissue engineered constructs (TECs) and the culture process affect final tendon repair. However, there remain significant challenges in developing strategies that will lead to a clinically effective and commercially successful product. In an effort to increase repair quality, a better understanding of normal development, and how it differs from adult tendon healing, may provide strategies to improve tissue engineering. As tendon tissue engineering continues to improve, the field needs to employ more clinically relevant models of tendon injury such as degenerative tendons. We need to translate successes to larger animal models to begin exploring the clinical implications of our treatments. By advancing the models used to validate our TECs, we can help convince our toughest customer, the surgeon, that our products will be clinically efficacious. As we address these challenges in musculoskeletal tissue engineering, the field still needs to address the commercialization of products developed in the laboratory. TEC commercialization faces numerous challenges because each injury and patient is unique. This review aims to provide tissue engineers with a summary of important issues related to engineering tendon repairs and potential strategies for producing clinically successful products. PMID:21625053
Shearn, Jason T.; Kinneberg, Kirsten R.C.; Dyment, Nathaniel A.; Galloway, Marc T.; Kenter, Keith; Wylie, Christopher; Butler, David L.
Tendon tissue engineering: progress, challenges, and translation to the clinic.
The tissue engineering field has made great strides in understanding how different aspects of tissue engineered constructs (TECs) and the culture process affect final tendon repair. However, there remain significant challenges in developing strategies that will lead to a clinically effective and commercially successful product. In an effort to increase repair quality, a better understanding of normal development, and how it differs from adult tendon healing, may provide strategies to improve tissue engineering. As tendon tissue engineering continues to improve, the field needs to employ more clinically relevant models of tendon injury such as degenerative tendons. We need to translate successes to larger animal models to begin exploring the clinical implications of our treatments. By advancing the models used to validate our TECs, we can help convince our toughest customer, the surgeon, that our products will be clinically efficacious. As we address these challenges in musculoskeletal tissue engineering, the field still needs to address the commercialization of products developed in the laboratory. TEC commercialization faces numerous challenges because each injury and patient is unique. This review aims to provide tissue engineers with a summary of important issues related to engineering tendon repairs and potential strategies for producing clinically successful products. PMID:21625053
Shearn, J T; Kinneberg, K R; Dyment, N A; Galloway, M T; Kenter, K; Wylie, C; Butler, D L
Muscle tendon unit (MTU) transfer is a common procedure performed to restore hand function after peripheral nerve or spinal cord injury. The principles of MTU transfer established for hand surgery can be adopted to optimize the dynamic excursion of the temporalis tendon transfer procedure for facial reanimation. Additionally, the force generating ability of a transferred MTU depends on the ideal length-tension relationship of the donor muscle. There are unclear guideline for selecting the ideal tension at which a transferred MTU will generate maximum force and excursion and current practice often leads to overstretch and suboptimal actin myosin interaction. The use of intraoperative electrical stimulation is an option for determining the ideal tension to optimize excursion of transferred temporalis tendon units in simile restoration. Understanding the biomechanics and principles of MTU and applying it to the temporalis tendon transfer procedure is necessary to improve its use in facial reanimation. PMID:23208742
Boahene, Kofi D O
A 39-year-old woman sustained a small wound on the palm of her right hand, which quickly healed naturally; however, a month later pain and limited range of motion were noted in her right finger. Surgery revealed the radial half of the flexor digitorum superficialis (FDS) tendon was ruptured and formed a flap, which hooked at the entrance of the A1 pulley. The proximal stump was sutured to the remaining ulnar (normal) side of the FDS tendon. Locking occurs between the tendon flap and the tendon sheath; therefore, when there is no fibrous tendon sheath near the partially ruptured tendon, locking will not occur. PMID:25121943
Seki, Yasuhiro; Kuroda, Hiroshi
Attrition or rupture of digital extensor tendons due to carpal boss: report of 2 cases.
We present 2 cases that demonstrate the potential for tendon involvement in the presence of a�carpal boss. In the first, a patient presented with tendon rupture without antecedent pain. In the second, pain and tendon irritation prompted magnetic resonance imaging that revealed tendon fraying, which was confirmed at surgery. These cases illustrate the potential for tendinous sequelae of a carpal boss. Advanced imaging may be considered when tendon irritation is clinically suspected. Attention to the possibility of tendon rupture in the setting of an otherwise asymptomatic carpal boss is advised. PMID:24674613
Ghatan, Andrew C; Carlson, Erik J; Athanasian, Edward A; Weiland, Andrew J
Purpose: Delayed healing is a common problem whenever tendon allografts are used for tendon or ligament reconstruction. Repopulating the allograft with host cells may accelerate tendon regeneration, but cell penetration into the allograft tendon is limited. Processing the tendon surface with slits that guide cells into the allograft substrate may improve healing. The purpose of this study was to describe a surface modification of allograft tendon that includes slits to aid cell repopulation and lubrication to enhance tendon gliding. Methods: Canine flexor digitorum profundus tendons were used for this study. Cyclic gliding resistance was measured over 1000 cycles. Tensile stiffness was assessed for normal tendon, tendon decellularized with trypsin and Triton X-100 (decellularized group), tendon decellularized and perforated with multiple slits (MS group) and tendon decellularized, perforated with slits and treated with a carbodiimide-derivatized hyaluronic acid and gelatin (cd-HA-gelatin) surface modification (MS-SM group). To assess tendon repopulation, bone marrow stromal cells (BMSCs) were used in the decellularized and MS groups. DNA concentration and histology were evaluated and compared to normal tendons and nonseeded decellularized tendons. Results: The gliding resistance of the decellularized and MS groups was significantly higher compared with the normal group. There was no significant difference in gliding resistance between the decellularized and MS group. Gliding resistance of the normal group and MS-SM group was not significantly different. The Young's modulus was not significantly different among the four groups. The DNA concentration in the MS group was significantly lower than in normal tendons, but significantly higher than in decellularized tendons, with or without BMSCs. Viable BMSCs were found in the slits after 2 weeks in tissue culture. Conclusions: Tendon slits can successfully harbor BMSCs without compromising their survival and without changing tendon stiffness. Surface modification restores normal gliding function to the slit tendon. Clinical Relevance: A multislit tendon reseeded with BMSCs, with a surface treatment applied to restore gliding properties, may potentially promote tendon revitalization and accelerate healing for tendon or ligament reconstruction applications. PMID:24024566
Amadio, Peter C.; Thoreson, Andrew R.; An, Kai-Nan
Distal biceps tendon injuries--current treatment options.
Three percent of all biceps tendon ruptures occur at the distal aspect, where the tendon inserts into the radial tuberosity. Distal bicep tendon ruptures typically occur in middle-aged males after an eccentric extension load is applied to the elbow. Patients usually complain of a sudden, sharp, and painful tearing sensation in the antecubital region, with a palpable defect. The biceps squeeze and hook tests are specific maneuvers by which to diagnose distal biceps ruptures on physical examination. Magnetic resonance imaging (MRI) or ultrasound maybe be helpful to distinguish between partial and complete tears. Anatomic studies suggest there are two distinct insertions for the short and long heads of the distal biceps. The short head may be a more powerful flexor, and the long head may be a more powerful supinator. Nonoperative treatment typically results in loss of flexion and supination strength and endurance. Early anatomic re-attachment is the goal. Surgical approaches include one- or two-incision techniques, and tendon fixation methods include the use of suture anchors, bone tunnels, an endobutton, or biotenodesis screws. Biomechanical studies have shown that endobuttons have higher load-to-failure strengths, compared to the other fixation methods. However, clinical studies have demonstrated that patients do well regardless of surgical approach or fixation method. Possible complications include nerve injuries, heterotopic ossification, postoperative fracture, tendon rerupture, complex regional pain syndrome, and wound infection. Partial ruptures are significantly less common and initially can be treated conservatively. Chronic tears are more difficult to treat because of possible tendon retraction and poor tissue quality. Tendon grafts using semitendinosus, fascia lata, hamstring, Achilles (calcaneal), or flexor carpi radialis have been successfully used for length restoration in these cases. PMID:20632985
Quach, Tony; Jazayeri, Reza; Sherman, Orrin H; Rosen, Jeffrey E
Quantitative ultrasound (QUS) assessment of tissue properties for Achilles tendons
NASA Astrophysics Data System (ADS)
Quantitative ultrasound (QUS) techniques have recently been widely applied for the characterization of tissues. For example, they can be used for the quantification of Achilles tendon properties based on the broadband ultrasound attenuation (BUA) and the speed of sound (SOS) when the ultrasound wave passes through the tissues. This study is to develop an integrated system to investigate the properties of Achilles tendons using QUS images from UBIS 5000 (DMS, Montpellier, France) and B-mode ultrasound images from HDI 5000 (ATL, Ultramark, USA). Subjects including young (32 females and 17 males; mean age: 23.7 � 2.0) and middle-aged groups (8 female and 8 males; mean age: 47.3 � 8.5 s) were recruited and tested for this study. Only subjects who did not exercise regularly and had no record of tendon injury were studied. The results show that the BUA is significantly higher for the young group (45.2 � 1.6 dB MHz-1) than the middle-age group (40.5 � 1.9 dB MHz-1), while the SOS is significantly lower for the young (1601.9 � 11.2 ms-1) compared to the middle-aged (1624.1 � 8.7 m s-1). On the other hand, the thicknesses of Achilles tendons for both groups (young: 4.31 � 0.23 mm; middle age: 4.24 � 0.23 mm) are very similar. For one patient who had an Achilles tendon lengthening (ATL) surgery, the thickness of the Achilles tendon increased from 4 mm to 4.33 mm after the surgery. In addition, the BUA increased by about 7.2% while the SOS decreased by about 0.6%. In conclusion, noninvasive ultrasonic assessment of Achilles tendons is useful for assisting clinical diagnosis and for the evaluation of a therapeutic regimen.
Du, Yi-Chun; Chen, Yung-Fu; Chen, Pei-Jarn; Lin, Yu-Ching; Chen, Tainsong; Lin, Chii-Jeng
Optimizing the Topology of Tendon-Driven Fingers: Rationale, Predictions and Implementation
% by changing specific pulley sizes for specific routings. In addition, we validate these large gains sensitive to tendon routing and pulley size, but also that informed design of fingers with fewer tendons can
Valero-Cuevas, Francisco
Diclofenac Patch for Treatment of Mild to Moderate Tendonitis or Bursitis
Rotator Cuff Tendonitis; Bicipital Tendonitis; Subdeltoid Bursitis of the Shoulder; Subacromial Bursitis of the Shoulder; Medial Epicondylitis of the Elbow; Lateral Epicondylitis of the Elbow; DeQuervain's Tenosynovitis of the Wrist
Intratendinous Tophaceous Gout Imitating Patellar Tendonitis in an Athletic Man
Patellar tendon-related pain is common in the athletic patient. When it occurs in skeletally mature patients participating in running, jumping, or kicking sports, the diagnosis of jumper�s knee patellar tendonitis is usually made. If patellar tendon pain is associated with a mass, the differential diagnosis should be broadened to include crystalline arthropathy. This article presents a case of a highly athletic 45-year-old man with a history of gout, anterior knee pain, and an enlarging mass in the region of the patellar tendon. Conservative management failed, and an excisional biopsy found it to be an intra-tendinous gouty tophus. To our knowledge, only 1 report exists documenting a patellar tendon mass secondary to gout, and no case report exists documenting this problem in an athlete. The interplay between athletics and gout has not been well described. Despite the long-term protective nature of fitness, transient elevations in uric acid associated with athletic endeavors may contribute acutely to manifestations of gout in some athletes. Resultant intra- or extra-articular pathology may present as, and easily be mistaken for, a sports-related injury. Without appropriate medical management, tophaceous deposition may continue to occur and treatment of the resultant mass may require surgical intervention. PMID:21410111
Gililland, Jeremy M.; Webber, Nicholas P.; Jones, Kevin B.; Randall, R. Lor; Aoki, Stephen K.
Hip extension strength following hamstring tendon harvest for ACL reconstruction.
Hamstring autograft harvest for ACL reconstruction may have an effect on hip extension strength and this may be important especially in sports that involve high speed running such as soccer, rugby, American football and the sprint disciplines of track and field. This aspect of hamstring tendon harvesting has not been looked at before. We have performed a non-randomised prospective case control study comparing isokinetic hip extension strength following four strand semitendinosus and gracilis tendons (4SHS) and bone-patellar tendon-bone (BPTB) autografts in ACL reconstruction. Isokinetic hip extension was assessed at 3 and 12 months post-operatively using a Kin-Com machine at a speed of 30 degrees per second. Three months post-operatively there was a significant decrease (p<0.05) in the peak force of concentric hip extension in the 4SHS group. There was no evidence that hip extension is weaker following ACL reconstruction with 4SHS tendon autograft than ACL reconstruction with BPTB autograft at 12 months post-operatively. We find no contra-indication to the use of 4SHS tendon autografts in ACL reconstruction in patients who wish to preserve hip extension strength for their sporting activities. PMID:17627827
Geoghegan, John M; Geutjens, Guido G; Downing, Nicholas D; Colclough, Karen; King, Richard J
Ultrasound Echo is Related to Stress, Strain in Tendon
The mechanical behavior of tendons has been well studied in vitro. A noninvasive method to acquire mechanical data would be highly beneficial. Elastography has been a promising method of gathering in vivo tissue mechanical behavior, but it has inherent limitations. This study presents acoustoelasticity as an alternative ultrasound-based method of measuring tendon stress and strain by reporting a relationship between ultrasonic echo intensity (B mode ultrasound image brightness) and mechanical behavior of tendon in vitro. Porcine digital flexor tendons were cyclically loaded in a mechanical testing system while ultrasonic echo response was recorded. We report that echo intensity closely follows the applied cyclic strain pattern in time with higher strain protocols resulting in larger echo intensity changes. We also report that echo intensity is related nonlinearly to stress and nearly linearly to strain. This indicates that ultrasonic echo intensity is related to the mechanical behavior in a loaded tissue by an acoustoelastic response, as previously described in homogeneous, nearly incompressible materials. Acoustoelasticity is therefore able to relate strain-dependent stiffness and stress to the reflected echo, even in the processed B-mode signals reflected from viscoelastic, inhomogeneous material such as tendon, and is a promising metric to acquire in vivo mechanical data noninvasively. PMID:21030024
Duenwald, Sarah; Kobayashi, Hirohito; Frisch, Kayt; Lakes, Roderic; Vanderby, Ray
In vivo behaviour of human muscle tendon during walking.
In the present study we investigated in vivo length changes in the fascicles and tendon of the human gastrocnemius medialis (GM) muscle during walking. The experimental protocol involved real-time ultrasound scanning of the GM muscle, recording of the electrical activity of the muscle, measurement of knee- and ankle-joint rotations, and measurement of ground reaction forces in six men during walking at 3 km h(-1) on a treadmill. Fascicular lengths were measured from the sonographs recorded. Musculotendon complex length changes were estimated from anatomical and joint kinematic data. Tendon length changes were obtained combining the musculotendon complex and fascicular length-change data. The fascicles followed a different length-change pattern from those of the musculotendon complex and tendon throughout the step cycle. Two important features emerged: (i) the muscle contracted near-isometrically in the stance phase, with the fascicles operating at ca. 50 mm; and (ii) the tendon stretched by ca. 7 mm during single support, and recoiled in push-off. The behaviour of the muscle in our experiment indicates consumption of minimal metabolic energy for eliciting the contractile forces required to support and displace the body. On the other hand, the spring-like behaviour of the tendon indicates storage and release of elastic-strain energy. Either of the two mechanisms would favour locomotor economy PMID:11217891
Fukunaga, T.; Kubo, K.; Kawakami, Y.; Fukashiro, S.; Kanehisa, H.; Maganaris, C. N.
Spontaneous flexor tendon rupture in systemic lupus erythematosus: A case report.
Spontaneous flexor tendon rupture is an unusual complication of systemic lupus erythematosus (SLE) and has not previously been reported. While tendon ruptures in association with SLE have been focused on the previous studies, upper extremity tendon ruptures are infrequently reported in the literature. Here, we present an uncommon case of spontaneous flexor tendon rupture of the ring and little fingers in a patient with SLE and discuss the mechanism of injury and its surgical treatment. PMID:24950170
Oda, Ryo; Fujiwara, Hiroyoshi; Tokunaga, Daisaku; Kishida, Aiko; Taniguchi, Daigo; Seno, Takahiro; Kawahito, Yutaka; Kubo, Toshikazu
In this investigation, we show the presence of both free glutamate (microdialysis) and glutamate NMDAR1 receptors (immunohistochemical analyses of tendon biopsies), in tendons from patients with chronic Achilles tendon pain (Achilles tendinosis) and in controls (pain-free tendons). The NMDAR1 immunoreaction was usually confined to acetylcholinesterase-positive structures, implying that the reaction is present in nerves. Glutamate is a potent pain mediator
H�kan Alfredson; Sture Forsgren; Kim Thorsen; Martin Fahlstr�m; H�kan Johansson; Ronny Lorentzon
Simultaneous bilateral biceps tendon rupture: a case report with practical sonographic diagnosis.
Simultaneous bilateral complete tear of the biceps tendons is a rare clinical entity with challenging treatment approaches. Current diagnostic imaging of rupture of the biceps tendon has reverted to magnetic resonance imaging; however, in the recent years, sonography has been widely used in musculoskeletal practice. The authors present a case of simultaneous bilateral biceps tendon rupture diagnosed on the basis of fundamental sonographic findings of the torn biceps tendons. PMID:25122098
Babaei-Ghazani, Arash; Eftekhar-Sadat, Bina; Ghabili, Kamyar
Characterization of collagens and proteoglycans at the insertion of the human achilles tendon
This study provides a unique correlation between a molecular biological and biochemical analysis of the extracellular matrix (ECM) macromolecules in one half of 28 human Achilles tendons with an immunohistochemical study of the other. Both the insertion site and the mid-tendon were studied. The insertion (enthesis) is characterized by three distinctive fibrocartilages, two in the tendon (enthesial and sesamoid) and
Andrew D. Waggett; James R. Ralphs; Alvin P. L. Kwan; David Woodnutt; Michael Benjamin
The biomechanical and metabolic effects of a running regime on the Achilles tendon in the rat
The Achilles tendons of 192 albino rats were subjected to biomechemical and metabolic testing after a defined running period and compared with a control group. After 2, 4, 8, 12 and 16 weeks, the cross-sectional area, ultimate tensile strength and oxygen uptake of the Achilles tendons were determined. Different reactions were demonstrated particularly after intensive training. These tendons showed an
H.-M. Sommer
Sclerosing therapy in chronic Achilles tendon insertional pain-results of a pilot study
The origin of Achilles tendon insertional pain has not been clarified. Treatment is considered difficult, though tendon, bone, and bursae, alone or in combination, may all be the source of pain. Recently, neovascularisation in the area with tendon changes was shown to correlate with pain in patients with chronic mid-portion Achilles tendinosis. In a pilot study, sclerosing the neovessels outside
Lars �hberg; H�kan Alfredson
Increased content of type III collagen at the rupture site of human Achilles tendon
We compared the type I and III collagen amounts and cross-linked telopeptides at the rupture site and two other sites of the same tendon. Tendon samples of ten individuals with total Achilles tendon rupture and six healthy cadavers were collected. The newly synthesized type I and III procollagens were assessed by extracting the soluble propeptides PINP, PICP and PIIINP. The
Heidi A. Eriksen; Ari Pajala; Juhana Leppilahti; Juha Risteli
Viscoelastic properties of muscle-tendon unitsThe biomechanical effects of stretching
Most muscle stretching studies have focused on defin ing the biomechanical properties of isolated elements of the muscle-tendon unit or on comparing different stretching techniques. We developed an experimental model that was designed to evaluate clinically relevant biomechanical stretching properties in an entire muscle- tendon unit. Our objectives were to characterize the viscoelastic behavior of the muscle-tendon unit and to
Dean C. Taylor; James D. Dalton; Anthony V. Seaber; William E. Garrett
Effect of pulley integrity on excursions and work of flexion in healing flexor tendons
We investigated the effect of incision of a single critical pulley on excursions and work of flexion in healing flexor tendons. Forty-two long toes from 21 white leghorn chickens were used as the experimental model. Gliding excursions of the flexor digitorum profundus tendons and work of flexion of the long toes were studied 8 weeks after tendon repair to determine
Jin Bo Tang; You Hua Wang; Yu Tong Gu; Feng Chen
Effect of A3 pulley and adjacent sheath integrity on tendon excursion and bowstringing
The effect of the A3 pulley and adjacent sheath integrity on tendon function at the proximal interphalangeal (PIP) joint was investigated in 21 fingers in 7 fresh-frozen cadaver hands. Excursions of the flexor digitorum profundus (FDP) tendons were measured when the tendons were pulled to produce PIP joint flexion of 110� from a resting position of 0�. Excursions of the
Jin Bo Tang; Ren Gou Xie
This study evaluated the insertional anatomy and orientation of the biceps tuberosity and tendon to assess the anatomic validity of repairs made with 1 incision vs 2 incisions. Computed axial tomography was used to image 30 cadaver radii, and each tendon insertion was measured with a digital micrometer. Specimens were sectioned and imaged with Faxitron radiography (Faxitron X-Ray Corp, Wheeling, IL) to determine the angular orientation of the biceps tendon insertion relative to the tuberosity apex. The tuberosity axis of orientation averaged 65 degrees (range, 15 degrees -120 degrees ) of pronation from anterior, with angular orientation encompassing a mean 59 degrees (range, 15 degrees -100 degrees ) arc with the midpoint of the insertion averaging 50 degrees (range, -5 degrees to 105 degrees ). Most biceps tendons inserted on the anterior aspect of the apex of the tuberosity, with an average width of 7 mm and length of 22 mm. The biceps tuberosity is oriented in more pronation than is typically described, prohibiting anatomic reinsertion of the tendon in 35% of specimens with current single-incision techniques. PMID:18325797
Forthman, Christopher L; Zimmerman, Ryan M; Sullivan, Michael J; Gabel, Gerard T
Morpho-functional changes in human tendon tissue.
Insertion tissue biopsies of right arm common extensor tendons from 11 patients with chronic lateral epicondylitis were processed for light and electron microscopy. The subjects were aged between 38 and 54 years (only one was 25). The specimens showed a variety of structural changes such as biochemical and spatial alteration of collagen, hyaline degeneration, loss of tenocytes, fibrocartilage metaplasia, calcifying processes, neovascularization and vessel wall modifications. Tissue alterations were evident in limited zones of the tendon fibrocartilage in which the surgical resection was generally visible. The areas where the degenerative processes were localized, were restricted and in spatial contiguity with morphologically normal ones. The observed cases presented histological and electron microscopic findings that characterize lateral epicondylitis as a degenerative phenomenon involving all tendon components. PMID:12044045
Galliani, I; Burattini, S; Mariani, A R; Riccio, M; Cassiani, G; Falcieri, E
Surgical treatment options for patella tendon rupture, Part I: Acute.
Patella tendon rupture is a debilitating injury. Prompt diagnosis and treatment is essential to prevent retraction of the patella with subsequent adhesions and quadriceps contractures. In a young patient with an acute rupture, primary repair usually is possible with various methods described to protect the repair. In acute injuries with inadequate tissue, augmentation with hamstring tendons or allograft generally is necessary. Because of the different types of rupture and the possibility for poor quality tissue, the surgeon should always be prepared to combine different techniques to obtain tthe best repair. Continuous passive motion generally can be initiated early with a secure repair. In patients with a patella tendon ruptured that is promptly diagnosed, securely repaired, and followed closely through their rehabilitation, good results can be expected. PMID:16119282
Greis, Patrick E; Holmstrom, Michael C; Lahav, Amit
Subcoracoid impingement and subscapularis tendon: is there any truth?
Summary Subcoracoid impingement and stenosis have been described related to anterior shoulder pain and subscapularis tendon tears, but the pathogenesis and related treatment of this condition has still not been explained properly. Variability of coracoid morphology has been described and both traumatic and iatrogenic factors can modify it. Some authors referred this to a primary narrow coracohumeral distance with different threshold values defined as increased risk factor for subscapularis and antero-superior RC tear; opposite theories stated that the stenosis is secondary to an anterosuperior translation of the humeral head toward the coracoid due to degenerative changes of the rotator cuff tendons. Limited coracoplasty can be performed when related risk factors are identified; however no clear consensus arises from specific literature review and extensive clinical and instrumental examination of the patient should be performed in order to identify specific risk factors for subscapularis tendon pathology and, subsequently, tailor the proper approach. PMID:23888292
Osti, Leonardo; Soldati, Francesco; Del Buono, Angelo; Massari, Leo
Subcoracoid impingement and subscapularis tendon: is there any truth?
Subcoracoid impingement and stenosis have been described related to anterior shoulder pain and subscapularis tendon tears, but the pathogenesis and related treatment of this condition has still not been explained properly. Variability of coracoid morphology has been described and both traumatic and iatrogenic factors can modify it. Some authors referred this to a primary narrow coracohumeral distance with different threshold values defined as increased risk factor for subscapularis and antero-superior RC tear; opposite theories stated that the stenosis is secondary to an anterosuperior translation of the humeral head toward the coracoid due to degenerative changes of the rotator cuff tendons. Limited coracoplasty can be performed when related risk factors are identified; however no clear consensus arises from specific literature review and extensive clinical and instrumental examination of the patient should be performed in order to identify specific risk factors for subscapularis tendon pathology and, subsequently, tailor the proper approach. PMID:23888292
Osti, Leonardo; Soldati, Francesco; Del Buono, Angelo; Massari, Leo
Torque resolver design for tendon-driven manipulators
Given a set of desired joint torques in an n-DOF tendon-driven manipulator with n + 1 control tendons, the determination of tendon forces is an indeterminate problem. Usually, the pseudo-inverse technique is used to solve for such a problem. In this paper, rather than using the pseudo-inverse technique is used to solve for such a problem. In this paper, rather than using the pseudo-inverse technique, an efficient methodology for transforming joint torques (n elements) to motor torques (n + 1 elements) has been developed. This technique called torque resolver'', utilizes two circuit-like operators to transform torques between the two different vector spaces. It can be easily programmed on a digital computer or implemented into an analog-circuit system. It is hoped that this technique will make real-time computed-torque control feasible. The technique has been demonstrated through the dynamic simulation of a three-DOF manipulator.
Lee, J.J.; Tsai, Lung-Wen.
Torque resolver design for tendon-driven manipulators
Given a set of desired joint torques in an n-DOF tendon-driven manipulator with n + 1 control tendons, the determination of tendon forces is an indeterminate problem. Usually, the pseudo-inverse technique is used to solve for such a problem. In this paper, rather than using the pseudo-inverse technique is used to solve for such a problem. In this paper, rather than using the pseudo-inverse technique, an efficient methodology for transforming joint torques (n elements) to motor torques (n + 1 elements) has been developed. This technique called ``torque resolver``, utilizes two circuit-like operators to transform torques between the two different vector spaces. It can be easily programmed on a digital computer or implemented into an analog-circuit system. It is hoped that this technique will make real-time computed-torque control feasible. The technique has been demonstrated through the dynamic simulation of a three-DOF manipulator.
Lee, J.J.; Tsai, Lung-Wen
Presence of lymphatics in a rat tendon lesion model.
Tendons lack sufficient blood supply and represent a bradytroph tissue with prolonged healing time under pathological conditions. While the role of lymphatics in wound/defect healing in tissues with regular blood supply is well investigated, its involvement in tendon defects is not clear. We here try to identify the role of the lymphatic system in a tendon lesion model with morphological methods. A rat Achilles tendon lesion model (n�=�5) was created via surgical intervention. Two weeks after surgery, animals were killed and lesioned site removed and prepared for polarization microscopy (picrosirius red) and immunohistochemistry using the lymphatic markers PROX1, VEGFR3, CCL21, LYVE-1, PDPN, and the vascular marker CD31. Additionally, DAPI was applied. Untreated tendons served as controls, confocal laser-scanning microscopy was used for documentation. At the lesion site, polarization microscopy revealed a structural reintegration while immunohistochemistry detected band-like profiles immunoreactive for PDPN, VEGFR3, CCL21, LYVE1, and CD31, surrounding DAPI-positive nuclei. PROX1-positive nuclei were detected within the lesion forming lines and opposed to each other. These PROX1-positive nuclei were surrounded by LYVE-1- or VEGFR3-positive surfaces. Few CD31-positve profiles contained PROX1-positive nuclei, while the majority of CD31-positive profiles lacked PROX1-positive nuclei. VEGFR3-, PDPN-, and LYVE-1-positive profiles were numerous within the lesion site, but absent in control tissue. Within 2�weeks, a structural rearrangement takes place in this lesion model, with dense lymphatic supply. The role of lymphatics in tendon wound healing is unclear, and proposed model represents a good possibility to study healing dynamics and lymphangiogenesis in a tissue almost completely lacking lymphatics in physiological conditions. PMID:25371325
Tempfer, Herbert; Kaser-Eichberger, Alexandra; Korntner, Stefanie; Lehner, Christine; Kunkel, Nadja; Traweger, Andreas; Trost, Andrea; Strohmaier, Clemens; Bogner, Barbara; Runge, Christian; Bruckner, Daniela; Krefft, Karolina; Heindl, Ludwig M; Reitsamer, Herbert A; Schr�dl, Falk
Prediction of the elastic strain limit of tendons.
The elastic strain limit (ESL) of tendons is the point where maximum elastic modulus is reached, after which micro-damage starts. Study of damage progression in tendons under repetitive (fatigue) loading requires a priori knowledge about ESL. In this study, we propose three different approaches for predicting ESL. First, one single value is assumed to represent the ESL of all tendon specimens. Second, different extrapolation curves are used for extrapolating the initial part of the stress-strain curve. Third, a method based on comparing the shape of the initial part of the stress-strain curve of specimens with a database of stress-strain curves is used. A large number of porcine tendon explants (97) were tested to examine the above-mentioned approaches. The variants of the third approach yielded significantly (p<0.05) smaller error values as compared to the other approaches. The mean absolute percentage error of the best-performing variant of the shape-based comparison was between 8.14�6.44% and 9.96�9.99% depending on the size of the initial part of the stress-strain curves. Interspecies generalizability of the best performing method was also studied by applying it for prediction of the ESL of horse tendons. The ESL of horse tendons was predicted with mean absolute percentage errors ranging between 10.53�7.6% and 19.16�14.31% depending on the size of the initial part of the stress-strain curves and the type of normalization. The results of this study suggest that both ESL and the shape of stress-strain curves may be highly different between different individuals and different anatomical locations. PMID:24362243
Reyes, A M; Jahr, H; van Schie, H T M; Weinans, H; Zadpoor, A A
Fat and fatty acids in muscle and adipose tissues are among the major factors influencing meat quality particularly nutritional value and palatability. The present study was carried out to examine the effects of supplementing inorganic selenium (Se), iodine (I) and a combination of both on fatty acid compositions in serum, and supraspinatus (SS), longissimus lumborum (LL), and semitendinosus (ST) muscles in goats. Twenty-four, 7 to 8 months old, Kacang male goats with a mean live weight of 22.00�1.17 kg were individually and randomly assigned into four groups of six animals each for 100 d of feeding prior to slaughter. The animals were offered the same concentrate (basal) diet as 1% of body weight with ad libitum amount of fresh guinea grass. The four groups were as follows: T1 (control) - basal diet without supplementation; T2 - basal diet with 0.6 mg Se/kg DM; T3 - basal diet with 0.6 mg I/kg DM; T4 - basal diet with combination of 0.6 mg Se/kg DM and 0.6 mg I/kg DM. The major fatty acids (FAs) detected in the serum were palmitic (C16:0), stearic (C18:0), oleic (C18:1n9) and linoleic (C18:2n-6), while the major FAs in the selected muscles were C16:0, C18:0 and C18:1n9 acids. The main polyunsaturated fatty acids (PUFA) detected in muscles and serum were (CI8:2n-6), linolenic acid (C18:3n-3), and arachidonic acid (C20:4n-6). No significant differences (p>0.05) were observed in the concentration of total saturated fatty acids (SFA) among the four groups. PUFA concentrations in the goats supplemented with Se (T2) were significantly higher (p<0.05) than the goats of the control group (T1). The PUFA: SFA ratio was significantly higher in the animals supplemented with dietary Se (T2) than those of control ones (T1). It is concluded that dietary supplementation of inorganic Se increased the unsaturated fatty acids in muscle. The supplementation of iodine with or without Se had negligible effects on muscle fatty acid content of Kacang crossbred male goats. PMID:25049986
Aghwan, Z. A.; Alimon, A. R.; Goh, Y. M.; Nakyinsige, K.; Sazili, A. Q.
Stiffness Ellipse Control of Tendon Mechanisms with Nonlinear Springs
NASA Astrophysics Data System (ADS)
Versatile and safe manipulators are required for use in human environments. A tendon mechanism with nonlinear springs that can mechanically adjust joint stiffness is one candidate that can satisfy the requirements of versatility and safety. In this paper, a hybrid stiffness ellipse control for controlling both mechanical and control stiffness at the end of the manipulator is proposed for the tendon mechanisms. This study shows the transformation of the stiffness ellipse at the ends of arms to joint stiffness. The transformation is applied to both mechanical joint stiffness and controller gain of joint angle controller. Simulation results verify the validity of the proposed method.
Okumura, Fumihiro; Komada, Satoshi; Hirai, Junji
The In Vitro Elution Characteristics of Vancomycin from Tendons
Background��Infection after ACL reconstruction is uncommon but catastrophic. Prophylactic graft saturation in vancomycin reportedly reduces\\u000a infection rates.\\u000a \\u000a \\u000a \\u000a \\u000a Questions\\/purposes��We characterized vancomycin elution from soaked tendons. Specifically, the effect of rinsing was studied. We also determined\\u000a how vancomycin concentration in the soak solution and tendon dimension influenced this elution rate, and examined whether\\u000a the vancomycin amount released was lower than osteoblast and
Jane E. Grayson; Gary D. Grant; Shailendra Dukie; Christopher J. Vertullo
Biomechanical risk factors and flexor tendon frictional work in the cadaveric carpal tunnel.
Pathological changes in carpal tunnel syndrome patients include fibrosis and thickening of the subsynovial connective tissue (SSCT) adjacent to the flexor tendons in the carpal tunnel. These clinical findings suggest an etiology of excessive shear-strain force between the tendon and SSCT, underscoring the need to assess tendon gliding characteristics representative of repetitive and forceful work. A mechanical actuator moved the middle finger flexor digitorum superficialis tendon proximally and distally in eight fresh frozen cadaver arms. Eighteen experimental conditions tested the effects of three well-established biomechanical predictors of injury, including a combination of two wrist postures (0� and 30� flexion), three tendon velocities (50, 100, 150mm/sec), and three forces (10, 20, 40N). Tendon gliding resistance was determined with two light-weight load cells, and integrated over tendon displacement to represent tendon frictional work. During proximal tendon displacement, frictional work increased with tendon velocity (58.0% from 50-150mm/sec). There was a significant interaction between wrist posture and tendon force. In wrist flexion, frictional work increased 93.0% between tendon forces of 10 and 40N. In the neutral wrist posture, frictional work only increased 33.5% (from 10-40N). During distal tendon displacement, there was a similar multiplicative interaction on tendon frictional work. Concurrent exposure to multiple biomechanical work factors markedly increased tendon frictional work, thus providing a plausible link to the pathogenesis of work-related carpal tunnel syndrome. Additionally, our study provides the conceptual basis to evaluate injury risk, including the multiplicative repercussions of combined physical exposures. PMID:25553671
Kociolek, Aaron M; Tat, Jimmy; Keir, Peter J
Tendon material properties vary and are interdependent among turkey hindlimb muscles
SUMMARY The material properties of a tendon affect its ability to store and return elastic energy, resist damage, provide mechanical feedback and amplify or attenuate muscle power. While the structural properties of a tendon are known to respond to a variety of stimuli, the extent to which material properties vary among individual muscles remains unclear. We studied the tendons of six different muscles in the hindlimb of Eastern wild turkeys to determine whether there was variation in elastic modulus, ultimate tensile strength and resilience. A hydraulic testing machine was used to measure tendon force during quasi-static lengthening, and a stress�strain curve was constructed. There was substantial variation in tendon material properties among different muscles. Average elastic modulus differed significantly between some tendons, and values for the six different tendons varied nearly twofold, from 829�140 to 1479�106 MPa. Tendons were stretched to failure, and the stress at failure, or ultimate tensile stress, was taken as a lower-limit estimate of tendon strength. Breaking tests for four of the tendons revealed significant variation in ultimate tensile stress, ranging from 66.83�14.34 to 112.37�9.39 MPa. Resilience, or the fraction of energy returned in cyclic length changes was generally high, and one of the four tendons tested was significantly different in resilience from the other tendons (range: 90.65�0.83 to 94.02�0.71%). An analysis of correlation between material properties revealed a positive relationship between ultimate tensile strength and elastic modulus (r2=0.79). Specifically, stiffer tendons were stronger, and we suggest that this correlation results from a constrained value of breaking strain, which did not vary significantly among tendons. This finding suggests an interdependence of material properties that may have a structural basis and may explain some adaptive responses observed in studies of tendon plasticity. PMID:22771746
Matson, Andrew; Konow, Nicolai; Miller, Samuel; Konow, Pernille P.; Roberts, Thomas J.
Spontaneous ruptures of the extensor mechanism of the knee are very rare. They tend to increase considerably in patients with metabolic diseases such as chronic renal failure, hyperparathyroidism, diabetes, gout, and systemic lupus erythematosus. The reported case regards a 48-year-old man with chronic, spontaneous and simultaneous quadriceps, and contra-lateral patellar tendon rupture. The patient suffered from chronic renal failure and for the past year from tertiary hyperparathyroidism. Ruptured tendons were repaired and both knee were evaluated monthly for the next 12�months. Good functional recovery was achieved on both knees without relapse. This case emphasizes the importance of long-term high parathyroid hormone level in the etiology of tendons ruptures. PMID:19384613
Grecomoro, Giuseppe; Martorana, Umberto
Many techniques have been described for the treatment of an acute achilles tendon rupture, but there is unfortunately no agreement between orthopedic surgeons regarding the best repair technique and post-treatment rehabilitation protocol. Overall, the surgical methods can be classified as either an open procedure or as a percutaneous procedure. While numerous techniques have been described for open surgical procedures, the strength of the repaired tendon, the healing time, the rerupture rates, and the changes in the range of motion due to adhesions may be the ultimate determining factors of the success of the procedure. In this case study, we report the results of treating a 35-year-old patient who suffered an achilles tendon rupture by combining two recently described surgical methods into a novel repair technique.
Toker, Serdar; Kilincoglu, Volkan; Yurtgun, M.Fahri
Pain-free normal Achilles tendons and chronic painful Achilles tendons were examined by the use of antibodies against a general nerve marker (protein gene-product 9.5, PGP9.5), sensory markers (substance P, SP; calcitonin gene-related peptide, CGRP), and immunohistochemistry. In the normal tendons, immunoreactions against PGP9.5 and against SP\\/CGRP were encountered in the paratendinous loose connective tissue, being confined to nerve fascicles and
Dennis Bjur; H�kan Alfredson; Sture Forsgren
The purpose of the study was to contribute to the mapping of molecular events during flexor tendon healing, in particular the growth factors insulin-like growth factor-1 (IGF-1), vascular endothelial growth factor (VEGF) and nerve growth factor (NGF), matrix metalloproteinases (MMP-3 and MMP-13) and their inhibitors (tissue inhibitors of metalloproteinases, TIMP-1 and TIMP-3, and the protease cathepsin K. In a rabbit model of flexor tendon injury, the mRNA expression for the growth factors, MMPs and TIMPs were measured in tendon and tendon sheath tissue at several time points (3, 6, 21, and 42 days) representing different phases of the healing process. We found that MMP-13 remained increased during the study period, whereas MMP-3 returned to normal levels within the first week after injury. TIMP-3 was down-regulated in the tendon sheaths. Cathepsin K was up-regulated in tendons and sheaths after injury. NGF was present in both tendons and sheaths, but unaltered. IGF-1 exhibited a late increase in the tendons, while VEGF was down-regulated at the later time points. In conclusion, we have demonstrated the presence of NGF in flexor tendons. MMP-13 expression appears to play a more protracted role in flexor tendon healing than MMP-3. The relatively low levels of endogenous IGF-1 and VEGF mRNA following injury support their potential beneficial role as exogenous modulators to optimize tendon healing and strength without increasing adhesion formation. PMID:21246620
Berglund, M E; Hart, D A; Reno, C; Wiig, M
Anisotropy in Tendon Investigated in Vivo by a Portable NMR Scanner, the NMR-MOUSE
NASA Astrophysics Data System (ADS)
Ordered tissue like tendon is known to exhibit the magic-angle phenomenon in magnetic resonance investigations. Due to the anisotropic structure the transverse relaxation time T2 depends on the orientation of the tendon in the magnetic field. In medical imaging, relaxation measurements of tendon orientation are restricted by the size of the object and the space available in the magnet. For humans, tendon orientation can only be varied within small limits. As a consequence, the magic-angle phenomenon may lead to a misjudgement of tendon condition. It is demonstrated that the NMR-MOUSE (mobile universal surface explorer), a hand-held NMR sensor, can be employed to investigate the anisotropy of T2 in Achilles tendon in vivo. The NMR-MOUSE provides a convenient tool for analyzing the correlation of T2 and the physical condition of tendon.
Haken, R.; Bl�mich, B.
Isolated rupture of the subscapularis tendon in an arm wrestler.
Rotator cuff injuries, especially in athletes, can be very disabling. A case of an isolated rupture of the subscapularis tendon in an arm wrestler is reported. Preoperative arthrogram and CT scan with intraoperative pictures are used to illustrate the pathology. Recommendation for treatment is surgical repair. PMID:3387331
Biondi, J; Bear, T F
Ultrasound diagnosis of Achilles tendon pathology in runners
The great upsurge in popularity of running activities has increased the number of athletes presenting with pathology of the Achilles tendon. A clinical and ultrasonic study was performed on 47 middle and long distance runners referred to the Authors with such problems. The results of this study can be grouped as follows: 1. paratendonitis: enlargement of the antero-posterior diameter of
N Maffulli; R Regine; M Angelillo; G Capasso; S Filice
Changes in the Achilles tendon reflexes following Skylab missions
NASA Technical Reports Server (NTRS)
Postflight measurements of Achilles tendon reflex duration on Skylab crewmen indicate a state of disequilibrium between the flexor and extensor muscle groups with an initial decrease in reflex duration. As the muscles regain strength and mass there occurs an overcompensation reflected by increased reflex duration. Finally, when a normal neuromuscular state is reached the reflex duration returns to baseline value.
Baker, J. T.; Nicogossian, A. E.; Hoffler, G. W.; Johnson, R. L.; Hordinsky, J. R.
Intracapsular origin of the long head of the biceps tendon
A developmental anomaly of the long head of the biceps tendon was found in a cadaveric shoulder. Findings on arthroscopy,\\u000a routine MR imaging, and MR arthrography were compared and correlated with results of anatomic dissection. MR arthrography\\u000a appears to be a very good diagnostic imaging method for depicting this anomaly prior to arthroscopy.
LeeRen Yeh; Robert Pedowitz; Sandy Kwak; Parviz Haghighi; Claus Muhle; Debra Trudell; D. Resnick
Laser tissue welding and repair of digital flexor tendons
NASA Astrophysics Data System (ADS)
Injuries involving division of the flexor tendons of the hand are a common surgical problem. Sutured repairs must be strong enough to withstand early active movement. Experiments were designed to assess the strength of bonds formed between tendon sections as a result of heating (1) under controlled conditions in a water bath and (2) using a carbon dioxide laser (laser tissue welding). The load (N) and stress (N/cm2) required to disrupt thermal bonds between bovine tendon sections heated for 4 minutes in water peaked at 62 degrees Celsius (13N, 11.3N/cm2). Further experiments revealed the optimal time period for heating to be 9 minutes (21.5N, 20.6N/cm2). A threshold effect was apparent at these parameters. The in vitro strength of sutured, laser welded and sutured and laser welded tendon repairs was compared in a rabbit model. Laser welding alone did not produce repairs as strong as sutured repairs. It did, however, augment the strength of sutured repair. This effect was maximal at a power of 0.1 W.
Drew, P. J.; Kiernan, Michael N.; MacGregor, A. D.; Clement, Marc
Allograft reconstruction for symptomatic chronic complete proximal hamstring tendon avulsion.
Complete proximal hamstring tendon avulsion is an uncommon injury that can cause significant disability in young, athletic individuals. Surgical reattachment is recommended and can be performed on a delayed basis if the tissue is sufficiently mobile. We report 2-year follow up for two cases where interpositional allograft tissue was used for reconstruction because the tendon was too retracted for primary repair. Two 30-year-old patients with complete proximal hamstring avulsion at least 2 years earlier reported severe hamstring weakness and restrictions with respect to sport and recreational activities. Proximal hamstring tendon reconstruction with Achilles tendon allograft was performed for both patients. They were immobilized for 8 weeks with the hip in extension and the knee in flexion using a custom orthosis, followed by physical therapy and weight bearing as tolerated. The patients were followed for over 2 years after the surgery and were evaluated with physical examination, isokinetic strength testing and detailed questions about their function. Following the procedure, both patients returned to a more active lifestyle that was greatly improved with respect to participation in sport and function. This procedure should be considered as a salvage operation as the patients did not return to completely normal function and demonstrated hamstring weakness on the operated side. PMID:18682918
Marx, Robert G; Fives, Gregory; Chu, Samuel K; Daluiski, Aaron; Wolfe, Scott W
How obesity modifies tendons (implications for athletic activities)
Summary Background: obesity is a well recognized risk factor for dysmetabolic and cardiovascular diseases, but can also be associated to musculo-skeletal disorders. Methods: a search of English-language articles was performed using the key search terms �obesity� or �body mass index� combined with �tendon�, or �tendinopathy�, indipendently. Results: several studies show that, in obese subjects, tendons frequently undergo to degeneration, which can progress to a symptomatic stage, with pain and functional impairment. The main histopathologic findings are a relative paucity of small collagen fibrils, expression of an impaired remodeling process, deposition of lipid droplets which can abut to tendolipomatosis, and a disorganized architecture in the tension regions. Both load-bearing and non load-bearing tendons can be affected. This suggests that systemic factors play an important pathogenetic role. Indeed, adipose tissue releases several bioactive peptides and hormones (chemerin, lipocalin, leptin and adiponectin), and cytokines responsible of a systemic state of chronic low grade inflammation. Conclusion: Physical activity is strongly recommended to stop the progression of weight gain or to bring an obese individual into the normal weight range. Therefore, leisure sport activity is useful in obese subjects, but caution is mandatory, because tendons with sub-clinical damage, when submitted to overload, can easily reach the symptomatic threshold. PMID:25489546
Abate, Michele
Ciprofloxacin-induced tendinopathy of the gluteal tendons.
Fluoroquinolone-induced tendinopathy most commonly affects the Achilles tendon; however, involvement of several other tendons has been described. This is a case report of ciprofloxacin-induced tendinopathy of the gluteal tendons with MRI findings. An obese 25-year-old woman with no significant past medical history was diagnosed with acute pyelonephritis and was treated with intravenous ciprofloxacin. Shortly after her first dose of ciprofloxacin, she developed severe left hip pain and decreased range of motion. MRI of the hips showed bilateral tendinopathy of the gluteal muscle insertion. A diagnosis of ciprofloxacin-induced tendinopathy was made based on her MRI and a Naranjo score of 7. Ciprofloxacin was stopped and her pain quickly resolved. Fluoroquinolones cause tendinopathy in 0.14 % to 0.4 % of patients using these agents. Fluoroquinolone-associated tendinopathy is a serious adverse reaction that can affect many tendons and should be considered in any patient presenting with new musculoskeletal complaints and in whom there is a history of fluoroquinolone use within the preceding 6 months. PMID:25047394
Shimatsu, Kaumakaokalani; Subramaniam, Somasundaram; Sim, Helen; Aronowitz, Paul
The effects of different thicknesses and configurations of core sutures were studied in human cadaveric flexor tendon repairs. Both straight and cyclic load tests were employed.To exploit the full strength of 4\\/0 suture material, the Kessler repair using four locked single knots would seem to be appropriate.
Wrist tendon forces during different dynamic wrist motions
Purpose A common treatment of arthritis of the first carpometacarpal joint requires all or a portion of the flexor carpi radialis tendon (FCR) to be used as an interpositional graft. The purpose of this study was to examine the in vitro tendon forces in six wrist flexor and extensors to determine if their force contribution changes during different dynamic wrist motions along with a specific application to the FCR. Methods Sixty two fresh frozen cadaver wrists were tested in a wrist joint motion simulator. During wrist flexion-extension, radioulnar deviation, dart throwing and circumduction motions, the peak and average tendon forces were determined for the extensor carpi ulnaris, extensor carpi radialis brevis and longus, abductor pollicis longus, flexor carpi radialis and flexor carpi ulnaris. Results During a dart throwing motion, the mean and peak FCR forces were statistically less than during the other 3 motions. Conversely, the mean and peak flexor carpi ulnaris forces were statistically greater during the dart throwing motion than during the other 3 motions. Discussion Patients who have undergone a surgical procedure in which all or a portion of the FCR has been harvested, may experience a decrease in wrist strength with wrist motion as the FCR tendon normally applies force during wrist motion. The motion least likely to be affected by such surgery is the dart throwing motion when the force on the remaining FCR is minimized. PMID:20353863
Werner, Frederick W.; Short, Walter H.; Palmer, Andrew K.; Sutton, Levi G.
Calcific tendinitis of the gluteus maximus tendon (gluteus maximus tendinitis).
Seven cases of calcific tendinitis of the gluteus maximus tendon are presented. Awareness of the precise anatomic location of the calcific deposit is essential for the accurate diagnosis of this uncommon site of tendinitis. Clinically, the presenting complaint is that of pain. In some instances, however, the patients are asymptomatic and the calcification is an incidental finding. PMID:6844940
Wepfer, J F; Reed, J G; Cullen, G M; McDevitt, W P
Tendon abnormalities mimicking metastatic disease in patients with prostate cancer.
We present plain x-ray examination, bone scintigraphy, computed tomography, and magnetic resonance imaging of 2 patients diagnosed with prostate cancer who complained of hip pain. Bone scintigraphy was suggestive for metastases. Further radiologic investigation revealed benign etiologies for the hip pain; calcific tendinitis of the vastus lateralis and tendonosis of the gluteus medius tendon were visualized. PMID:17667430
Kerimoglu, Ulku; Kaya, Diana; Ergen, Fatma Bilge
Classification of rotator cuff tendinopathy using high definition ultrasound
Summary Background: ultrasound is a valid cost effective tool in screening for rotator cuff pathology with high levels of accuracy in detecting full-thickness tears. To date there is no rotator cuff tendinopathy classification using ultrasound. The aims of this study are to define a valid high-definition ultrasound rotator cuff tendinopathy classification, which has discriminate validity between groups based upon anatomical principles. Methods: 464 women, aged 65�87, from an established general population cohort underwent bilateral shoulder ultrasound and musculoskeletal assessment. Sonographer accuracy was established in a separate study by comparing ultrasound findings to the gold standard intra-operative findings. Results: there were 510 normal tendons, 217 abnormal tendons, 77 partial tears, and 124 full-thickness tears. There was no statistical difference in age or the proportion with pain between the abnormal enthesis and partial tear groups, however both groups were statistically older (p<0.001) and had a greater proportion with pain (p<0.001 & p=0.050) than normal tendons. The full-thickness tears were statistically older than normal tendons (p<0.001), but not abnormal/partially torn tendons. The proportion with pain was significantly greater than both groups (p<0.001 & p=0.006). Symptomatic shoulders had a larger median tear size than asymptomatic shoulders (p=0.006). Using tear size as a predictor of pain likelihood, optimum sensitivity and specificity occurred when dividing tears into groups up to 2.5cm and >2.5cm, which corresponds with anatomical descriptions of the width of the supraspinatus tendon. Conclusion: the classification system is as follows: Normal Tendons; Abnormal enthesis/Partial-thickness tear; Single tendon full-thickness tears (0�2.5cm); Multi-tendon full-thickness tears (>2.5cm). PMID:25489559
Hinsley, Hannah; Nicholls, Alex; Daines, Michael; Wallace, Gemma; Arden, Nigel; Carr, Andrew
Functional Consequence of Distal Brachioradialis Tendon Release: A Biomechanical Study
Purpose Open reduction and internal fixation of distal radius fractures often necessitates release of the brachioradialis from the radial styloid. However, this common procedure has the potential to decrease elbow flexion strength. To determine the potential morbidity associated with brachioradialis release, we measured the change in elbow torque as a function of incremental release of the brachioradialis insertion footprint. Methods In 5 upper extremity cadaveric specimens, the brachioradialis tendon was systematically released from the radius, and the resultant effect on brachioradialis elbow flexion torque was measured. Release distance was defined as the distance between the release point and the tip of the radial styloid. Results Brachioradialis elbow flexion torque dropped to 95%, 90% and 86% of its original value at release distances of 27mm, 46mm, and 52mm, respectively. Importantly, brachioradialis torque remained above 80% of its original value at release distances up to 7 centimeters. Conclusions Our data demonstrate that release of the brachioradialis tendon from its insertion has minor effects on its ability to transmit force to the distal radius. Clinical Relevance These data may imply that release of the distal brachioradialis tendon during distal radius open reduction internal fixation can be performed without meaningful functional consequences to elbow flexion torque. Even at large release distances, overall elbow flexion torque loss after brachioradialis release would be expected to be less than 5% due to the much larger contributions of the biceps and brachialis. Use of the brachioradialis as a tendon transfer donor should not be limited by concerns of elbow flexion loss, and the tendon could be considered as an autograft donor. PMID:23528425
Tirrell, Timothy F.; Franko, Orrin I.; Bhola, Siddharth; Hentzen, Eric R.; Abrams, Reid A.; Lieber, Richard L.
Muscle-tendon structure and dimensions in adults and children.
Muscle performance is closely related to the architecture and dimensions of the muscle-tendon unit and the effect of maturation on these architectural characteristics in humans is currently unknown. This study determined whether there are differences in musculo-tendinous architecture between adults and children of both sexes. Fascicle length and pennation angle were measured from ultrasound images at three sites along the length of the vastus intermedius, vastus lateralis, vastis medialis and rectus femoris muscles. Muscle volume and muscle-tendon length were measured from magnetic resonance images. Muscle physiological cross-sectional area (PCSA) was calculated as the ratio of muscle volume to optimum fascicle length. Fascicle length was greater in the adult groups than in children (P < 0.05) but pennation angle did not differ between groups (P > 0.05). The ratios between fascicle and muscle length and between fascicle and tendon length were not different (P > 0.05) between adults and children for any quadriceps muscle. Quadriceps volume and PCSA of each muscle were greater in adults than children (P < 0.01) but the relative proportion of each head to the total quadriceps volume was similar in all groups. However, the difference in PCSA between adults and children (men approximately 104% greater than boys, women approximately 57% greater than girls) was greater (P < 0.05) than the difference in fascicle length (men approximately 37% greater than boys, women approximately 10% greater than girls). It is concluded that the fascicle, muscle and tendon lengthen proportionally during maturation, thus the muscle-tendon stiffness and excursion range are likely to be similar in children and adults but the relatively greater increase in PCSA than fascicle length indicates that adult muscles are better designed for force production than children's muscles. PMID:20345856
O'Brien, Thomas D; Reeves, Neil D; Baltzopoulos, Vasilios; Jones, David A; Maganaris, Constantinos N
Tendon-to-bone healing is typically poor, with a high rate of repair-site rupture. Bone loss after tendon-to-bone repair may contribute to poor outcomes. Therefore, we hypothesized that the local application of the osteogenic growth factor BMP-2 would promote bone formation, leading to improved repair site mechanical properties. Intrasynovial canine flexor tendons were injured in Zone 1 and repaired into bone tunnels in the distal phalanx. BMP-2 was delivered to the repair site using either a calcium phosphate matrix (CPM) or a collagen sponge (COL) carrier. Each animal also received carrier alone in an adjacent repair to serve as an internal control. Repairs were evaluated at 21 days using biomechanical, radiographic, and histologic assays. Although an increase in osteoid formation was noted histologically, no significant increases in bone mineral density occurred. When excluding functional failures (i.e., ruptured and gapped repairs), mechanical properties were not different when comparing BMP-2/CPM groups with carrier controls. A significantly higher percentage of BMP-2 treated specimens were functional failures (maximum force < 20 N) compared to carrier controls. While tendon-to-bone healing can be enhanced by addressing the bone loss that typically occurs after surgical repair, the delivery of BMP-2 using the concentrations and methods of the current study did not improve mechanical properties over carrier alone. The anticipated anabolic effect of BMP-2 was insufficient in the short time frame of this study to counter the post-repair loss of bone. PMID:22618762
Thomopoulos, S; Kim, HM; Silva, MJ; Ntouvali, E; Manning, CN; Potter, R; Seeherman, H; Gelberman, RH
to design an artificial tendon that mimics the performance of the human Achilles tendon. The proposed tendon-28, 2000. Artificial Tendons: Biomechanical Design Properties for Prosthetic Lower Limbs Glenn K. email@example.com firstname.lastname@example.com Abstract - This paper reports on the design of an artificial tendon
Treatment of peroneal nerve injuries with simultaneous tendon transfer and nerve exploration
Background Common peroneal nerve palsy leading to foot drop is difficult to manage and has historically been treated with extended bracing with expectant waiting for return of nerve function. Peroneal nerve exploration has traditionally been avoided except in cases of known traumatic or iatrogenic injury, with tendon transfers being performed in a delayed fashion after exhausting conservative treatment. We present a new strategy for management of foot drop with nerve exploration and concomitant tendon transfer. Method We retrospectively reviewed a series of 12 patients with peroneal nerve palsies that were treated with tendon transfer from 2005 to 2011. Of these patients, seven were treated with simultaneous peroneal nerve exploration and repair at the time of tendon transfer. Results Patients with both nerve repair and tendon transfer had superior functional results with active dorsiflexion in all patients, compared to dorsiflexion in 40% of patients treated with tendon transfers alone. Additionally, 57% of patients treated with nerve repair and tendon transfer were able to achieve enough function to return to running, compared to 20% in patients with tendon transfer alone. No patient had full return of native motor function resulting in excessive dorsiflexion strength. Conclusion The results of our limited case series for this rare condition indicate that simultaneous nerve repair and tendon transfer showed no detrimental results and may provide improved function over tendon transfer alone. PMID:25099247
Release of the A4 pulley to facilitate zone II flexor tendon repair.
During primary or delayed primary repair of the flexor digitorum profundus tendon, surgeons often face difficulty in passing the retracted tendon or repaired tendon under the dense, fibrous A4 pulley. The A4 pulley is the narrowest part of the flexor sheath, proximal to the terminal tendon. Disrupted tendon ends (or surgically repaired tendons) are usually swelling, making passage of the tendons under this pulley difficult or even impossible. During tendon repair in the A4 pulley area, when the trauma is in the middle part of the middle phalanx and the A3 pulley is intact, the A4 pulley can be vented entirely to accommodate surgical repair and facilitate gliding of the repaired tendon after surgery. Venting the pulley does not disturb tendon function when the other major pulleys are intact and when the venting of the A4 pulley and adjacent sheath is limited to the middle half of the middle phalanx. Such venting is easily achieved through a palmar midline or lateral incision of the A4 pulley and its adjacent distal or/and proximal sheath, which helps ensure a more predictable recovery of digital flexion and extension. PMID:25282719
Tang, Jin Bo
Operative technique for human composite flexor tendon allograft procurement and engraftment.
Devastating volar hand injuries with significant damage to the pulley structures and fibro-osseous sheath, flexor tendons, and volar plates pose a major problem to the reconstructive hand surgeon. Despite advances in tendon handling, operative technique, and postoperative hand rehabilitation, patients who have undergone flexor tendon reconstruction are often plagued by chronic pain, stiffness, and decreased range of motion with resultant decreased ability to work and poor quality of life. Postoperative adhesion formation and lack of suitable donor material for tendon autograft are 2 fundamental problems that continue to challenge the hand surgeon. In 1967, Erle E. Peacock, Jr, described a technique of flexor tendon reconstruction using cadaveric composite flexor tendon allograft, which consisted of both the flexor digitorum profundus and superficialis tendons in their respective fibro-osseous sheaths consisting of the digital pulley structures and the underlying periosteum and volar plates. This technique never gained widespread acceptance due to concerns regarding tissue antigenicity, infectious disease transmission, and the rising popularity of the method of Hunter for silastic rod-based flexor tendon reconstruction initially described during the same period. With modern-day advances in tissue processing with acellularization and extensive donor screening for transmissible diseases, this technique should be revisited to address the reconstructive needs of patients with extensive volar soft tissue and tendon injury. Herein, we describe the operative technique of composite flexor tendon procurement and reconstruction with key modifications from the initial technique described by Peacock for improved composite construct elevation, soft tissue inset, and bony attachment. PMID:24691346
DeGeorge, Brent R; Rodeheaver, George T; Drake, David B
Adaptability of elderly human muscles and tendons to increased loading
Senile sarcopenia, the loss of muscle mass associated with aging, is one of the main causes of muscle weakness and reduced locomotor ability in old age. Although this condition is mainly driven by neuropathic processes, nutritional, hormonal and immunological factors, as well as a reduction in physical activity, contribute to this phenomenon. Sarcopenia alone, however, does not fully account for the observed muscle weakness, as the loss of force is greater than that accounted for by the decrease in muscle size. As a consequence, a reduction in the force per unit area, both at single fibre and at whole muscle level, is observed. We recently suggested that at whole muscle level, this reduction in intrinsic force is the result of the combined effect of changes in (1) muscle architecture, (2) tendon mechanical properties, (3) neural drive (reduced agonist and increased antagonist muscle activity) and (4) single fibre-specific tension. Whereas several studies support the role of the last two factors in the loss of intrinsic muscle force with aging, alterations in muscle architecture and in tendon mechanical properties have also been shown to contribute to the above phenomenon. Indeed, sarcopenia of the human plantarflexors, represented by a 25% reduction in muscle volume, was found to be associated with a 10% reduction in fibre fascicle length and 13% reduction in pennation angle. These architectural alterations were accompanied by a 10% decrease in tendon stiffness, attributable to alterations in tendon material properties, as suggested by a 14% decrease in Young's modulus. Most of these changes may be reversed by 14 weeks of resistive training; both fibre fascicle length and tendon stiffness were found to be increased by 10 and 64%, respectively. Surprisingly, however, training had no effect on the estimated relative length�tension properties of the muscle, indicating that the effects of greater tendon stiffness and increased fascicle length cancelled out each other. It seems that natural strategies may be in place to ensure that the relative operating range of muscle remains unaltered by changes in physical activity, in old age. PMID:16637869
Narici, Marco V; Maganaris, Constantinos N
Applied Joint-Space Torque and Stiffness Control of Tendon-Driven Fingers
NASA Technical Reports Server (NTRS)
Existing tendon-driven fingers have applied force control through independent tension controllers on each tendon, i.e. in the tendon-space. The coupled kinematics of the tendons, however, cause such controllers to exhibit a transient coupling in their response. This problem can be resolved by alternatively framing the controllers in the joint-space of the manipulator. This work presents a joint-space torque control law that demonstrates both a decoupled and significantly faster response than an equivalent tendon-space formulation. The law also demonstrates greater speed and robustness than comparable PI controllers. In addition, a tension distribution algorithm is presented here to allocate forces from the joints to the tendons. It allocates the tensions so that they satisfy both an upper and lower bound, and it does so without requiring linear programming or open-ended iterations. The control law and tension distribution algorithm are implemented on the robotic hand of Robonaut-2.
Abdallah, Muhammad E.; Platt, Robert, Jr.; Wampler, Charles W.; Hargrave, Brian
The musculoskeletal loading profile of the thumb during pipetting based on tendon displacement.
Strong evidence indicates that highly repetitive manual work is associated with the development of upper extremity musculoskeletal disorders (MSDs). One of the occupational activities that involves highly repetitive and forceful hand work is manual pipetting in chemical or biological laboratories. In the current study, we quantified tendon displacement as a parameter to assess the cumulative loading exposure of the musculoskeletal system in the thumb during pipetting. The maximal tendon displacement was found in the flexor pollicis longus (FPL) tendon. Assuming that subjects' pipetting rates were maintained constant during a period of 1 h, the average accumulated tendon displacement in the FPL reached 29 m, which is in the lower range of those observed in other occupational activities, such as typing and nail gun operations. Our results showed that tendon displacement data contain relatively small standard deviations, despite high variances in thumb kinematics, suggesting that the tendon displacements may be useful in evaluating the musculoskeletal loading profile. PMID:24018066
Wu, John Z; Sinsel, Erik W; Shroyer, Justin F; Welcome, Daniel E; Zhao, Kristin D; An, Kai-Nan; Buczek, Frank L
Traumatic Subscapularis Tendon Tear in an Adolescent American Football Player
Isolated traumatic subscapularis tendon tears are uncommon at any age. In adolescent patients, this type of injury is even more infrequent and usually presents as a bony avulsion of the lesser tuberosity. This report reviews a case of an adolescent American football player sustaining a posterior impact to an abducted, extended arm that resulted in an isolated subscapularis tendon tear. Magnetic resonance imaging of the shoulder revealed an isolated subscapularis tear retracted 1.6 cm without bony avulsion from the lesser tuberosity. Surgical repair was performed with 2 biocomposite absorbable anchors in the lesser tuberosity. The patient returned to basketball 12 weeks after surgery. This case illustrates that a high index of suspicion is required for an appropriate diagnosis in young athletes. PMID:24427400
Gibson, Margaret E.; Gurley, Daniel; Trenhaile, Scott
Double tendon transfer for correction of drop-foot.
Many conditions can cause foot drop, which makes walking difficult because the foot easily bumps into obstacles, or the knee must be kept more flexed than usual during the swing phase of gait, especially when going up stairs. Several techniques that have been described to correct foot drop rely on bone procedures or tendon transfer, with or without bone fixation. In this article, we describe a simple technique that is heavily used in leprosy-endemic countries and provides long-lasting results. It requires a double tendon transfer through the interosseous membrane of leg; the tibialis posterior and flexor digitorum longus are sutured to the tibialis anterior, and extensor hallucis longus and extensor digitorum longus, respectively, proximally to the extensor retinaculum. PMID:25623271
Grauwin, M-Y; Wavreille, G; Fontaine, C
Multiple Giant Cell Tumours of Tendon Sheath: A Rare Occurrence
Giant Cell Tumours Of Tendon Sheath (GCTTS) are the second most frequent soft tissue tumours affecting the hand with an overall incidence of 1 in 50,000 individuals. These tumours are usually localized and solitary, with multiple GCTTS occurring rarely. Multi-centric origin is considered unusual and very few cases of multiple GCTTS have been reported till date. Here, we report a rare case of a 26-year-old female who presented with multiple painless swellings on palmar aspect of little finger of right hand since six months. Clinical diagnosis of Dupuytren�s contracture was given. Intraoperative examination revealed multiple separate nodules, firmly attached to the flexor tendon synovial sheath. Histopathology showed features of GCTTS. PMID:24596760
Pathade, Smita Charandas; Kurpad, Ramkumar; Tauheed, Mohammed
[Effects of Gravity on Attachment of Tendon to Bone
NASA Technical Reports Server (NTRS)
We have received and processed all samples for either light or scanning electron microscopic analysis and have completed the histomorphometric analysis. We have characterized the changes caused by spaceflight to tendon attachments to the calcaneus, tibia, fibula and femur and compared them to hindlimbs and forelimbs from NIH.RZ. Soleus muscle histomorphometry has also been completed. Our results suggest severe osteoporosis in the femur, fibula and tibia of animals coincident to spaceflight, which had not resolved after 4-5 days following return to earth. This was evident at all sites, including sites of tendon attachments. This atrophy was not evident in the calcaneus. No muscle atrophy was evident. Comparison of scanning photomicrographs of flight animals with other lactating animals demonstrated structural similarities and suggested that it might be worthwhile to assess whether lactation is a factor in development of the osteoporosis in the spaceflight animals. In addition, evaluation of total calcium utilization by spaceflight animals would be beneficial.
Johnson, Roger B.
Long-term results of tendon shortening trapeziometacarpal arthroplasty.
Multiple soft tissue arthroplasties have been described for reconstruction of trapeziometacarpal arthritis. Trapeziectomy with abductor pollicis longus tendon shortening has been reported to have favorable short-term results, with 95% to 100% good or excellent pain relief at an average of 18 to 31 months. No long-term results of this reconstruction have been published. In the current study, 29 abductor pollicis longus shortening arthroplasties were reviewed at an average of 5.1 years. Although 83% of patients experienced good or excellent pain relief, pinch weakness, a small arthroplasty space, and first metacarpal instability were present in numerous patients. Because of these problems observed at long-term followup, the authors now use ligament reconstruction tendon interposition as the primary trapeziometacarpal arthroplasty. PMID:12461375
Budoff, Jeffrey E; Gordon, Leonard
Dynamic tracking of tendon elongation in ultrasound imaging
NASA Astrophysics Data System (ADS)
The aim of this study was to evaluate the elongation of the Achilles tendon by looking at the changing position of Myo-Tendenious Junction (MTJ) using ultrasound during isometric contraction on an Isometric dynamometer. A sequence of ultrasound images in the form of movie, obtained from a unit operating at a frequency of 12MHz during isometric contraction, was analyzed offline using MATLAB to track the MTJ. This investigation has implemented important techniques for in vivo feature extraction of Achilles tendon. Prior to feature extraction, the images were filtered by anisotropic diffusion method and morphological enhancements. The cross correlation search algorithm with an adaptive mask was utilized to track MTJ by comparing adjacent segmented frames. The present method was studied on seventeen subjects, where it was able to measure the related movement accurately.
Karimpoor, Mahta; Screen, Hazel; Morrissey, Dylan
Osmotic pressure induced tensile forces in tendon collagen
NASA Astrophysics Data System (ADS)
Water is an important component of collagen in tendons, but its role for the function of this load-carrying protein structure is poorly understood. Here we use a combination of multi-scale experimentation and computation to show that water is an integral part of the collagen molecule, which changes conformation upon water removal. The consequence is a shortening of the molecule that translates into tensile stresses in the range of several to almost 100?MPa, largely surpassing those of about 0.3?MPa generated by contractile muscles. Although a complete drying of collagen would be relevant for technical applications, such as the fabrication of leather or parchment, stresses comparable to muscle contraction already occur at small osmotic pressures common in biological environments. We suggest, therefore, that water-generated tensile stresses may play a role in living collagen-based materials such as tendon or bone.
Masic, Admir; Bertinetti, Luca; Schuetz, Roman; Chang, Shu-Wei; Metzger, Till Hartmut; Buehler, Markus J.; Fratzl, Peter
Diagnosing Achilles tendon injuries in the emergency department.
Achilles tendon (AT) injury is an overuse injury often seen in professional and recreational athletes. It tends to affect men, particularly those in their thirties and forties, more than women, and is typically seen in people who are intermittently active. To ensure AT ruptures are identified and treated effectively, early intervention in emergency departments (EDs) is crucial. This article discusses how advanced nurse practitioners can use their comprehensive problem-solving, clinical decision-making and clinical judgement skills to manage patients who present with suspected AT injury. It also describes the anatomy of tendon rupture, the aetiology and mechanism of injuries, and the importance of assessment and diagnostic tools, therapeutic techniques and management strategies. Finally, it considers the psychological effect this injury can have on patients, while in the ED and after discharge. A case study is included as an example of ED management. PMID:24024724
Gibbons, Lynda
Avoidance of unfavourable results following primary flexor tendon surgery
This review describes the biological problems faced by those managing primary flexor tendon injuries and explains why these problems still thwart attempts to achieve normal, or near normal, function after this injury, despite a century of surgical effort. It considers the historical background of the early 20th century attempts to improve the results and analyses the clinical usefulness of more recent research into tendon core and circumferential suture modification, including the authors� work in this field, and changes in post-operative mobilisation over the last 50 years. More recent manipulation of the sheath to improve results and the future possibility of manipulation of adhesions are discussed. It also discusses other factors, e.g., the patient, the experience of the surgeon, the use of therapists, the timing of repair, complex injuries, injuries in zones other than zone 2, which can have a bearing on the results and considers how these can be modified to avoid an unfavourable outcome. PMID:24501468
Elliot, D.; Giesen, T.
Tendon cell outgrowth rates and morphology associated with kevlar-49.
A rat tendon cell model was used to evaluate the in vitro biocompatibility of kevlar-49. The cell response to kevlar was compared to carbon AS-4 and nylon sutures. Three trials were run and cell growth rates were statistically similar for all the materials tested. A separate experiment was conducted in which the same fiber materials were placed in the same Petri dish. Again, the rates were similar for each material. Finally, the cells were observed with a scanning electron microscope, and the three classic cell morphologies associated with this tendon cell model were observed. Also, cellular attachment to the fiber and cellular encapsulation of the fiber were identical for the three materials tested. Kevlar-49 proved to be comparable to carbon AS4 and nylon sutures in terms of cellular response and cell outgrowth rates. PMID:3235468
Zimmerman, M; Gordon, K E
Anatomic variants of the peroneal tendons may cause tendon disorders. Moreover, there is a lack of evidence on how to address chronic tendon pathology when a variant of the peroneal tendons is causing the patient's symptoms. We present a patient with an uncommon peroneal muscle presentation: a single muscular belly dividing into both the peroneus longus and brevis tendons. After extensive debridement of tendinopathic tissue, primary repair or tenodesis was not possible; therefore a unique solution for this problem was performed, reconstructing both peroneal tendons using a semitendinosus allograft. PMID:25682415
Pellegrini, Manuel J; Adams, Samuel B; Parekh, Selene G
Giant cell tumor of the flexor hallucis longus tendon sheath: a case study.
Giant cell tumor of tendon sheath is infrequently documented in the foot and even less near the ankle. This case report involves such a tumor of the flexor hallucis longus tendon presenting at the posterior ankle. Diagnosis was aided by magnetic resonance imaging, and treatment consisted of complete surgical excision. Pathologic examination verified the diagnosis of giant cell tumor of tendon sheath, and follow-up magnetic resonance imaging revealed no remnants or recurrence of tumor 1 year after surgery. PMID:21406703
Findling, Jeff; Lascola, Natalie K; Groner, Thomas W
Evidence of accumulated stress in Achilles and anterior knee tendons in elite badminton players.
Tendon-related injuries are a major problem, but the aetiology of tendinopathies is unknown. In tendinopathies as well as during unaccustomed loading, intra-tendinous flow can be detected indicating that extensive loading can provoke intra-tendinous flow. The aim of present study is to evaluate the vascular response as indicated by colour Doppler (CD) activity in both the Achilles and patella tendon after loading during high-level badminton matches. The Achilles tendon was subdivided into a mid-tendon, pre-insertional, and insertional region and the anterior knee tendons into a quadriceps-, patella- and tuberositas region. Intra-tendinous flow was measured using both a semi-quantitative grading system (CD grading) and a quantitative scoring system (CF) on colour Doppler. Intra-tendinous flow in the Achilles and anterior knee tendons was examined in fourteen single players before tournament and after 1st and 2nd match, respectively on both the dominant and non-dominant side. All players had abnormal intra-tendinous flow (Colour Doppler�?�grade 2) in at least one tendon in at least one scan during the tournament. At baseline, only two of the 14 players had normal flow in all the tendons examined. After 1st match, tendencies to higher intra-tendinous flow were observed in both the dominant patella tendon and non-dominant quadriceps tendon (P-values n.s.). After 2nd match, intra-tendinous flow was significant increased in the dominant patella tendon (P�=�0.009). In all other locations, there was a trend towards a stepwise increase in intra-tendinous flow. The preliminary results indicate that high amount of intra-tendinous flow was found in elite badminton players at baseline and was increased after repetitive loading, especially in the patella tendon (dominant leg). The colour Doppler measurement can be used to determine changes in intra-tendinous flow after repetitive loading. PMID:20652535
Boesen, Anders Ploug; Boesen, Morten Ilum; Koenig, Merete Juhl; Bliddal, Henning; Torp-Pedersen, Soren; Langberg, Henning
The effect of antiseptic solution lavage on the palmar digital tendon sheath
State University; D. V. M. , Auburn University Chairman of Advisory Committee: Dr. Jeffrey P. Watkins Wounds entering a tendon sheath often become a very serious problem in the equine. Infection of the tendon sheath frequently causes inflammation... VITA . . . ~ ~ ~ ~ ~ ~ Page ~ 111 vr 1 2 7 16 53 60 63 V11') LIST OF TABLES Table Page Histologic inflammation scoring for each tendon sheath was based on a composite of the following parameters (scored by normal = 0, minimal = 1, mild...
Baird, Aubrey Nicholas
Development and Evaluation of Multiple Tendon Injury Models in the Mouse
The mouse has proven to be an advantageous animal model system in basic science research focused on aiding in development and evaluation of potential treatments; however, the small size of mouse tendons makes consistent and reproducible injury models and subsequent biomechanical evaluation challenging for studying tendon healing. In this study, we investigated the feasibility and reproducibility of multiple mouse tendon injury models. Our hypothesis was that incisional (using a blade) and excisional (using a biopsy punch) injuries would result in consistent differences in tendon material properties. At 16 weeks of age, 17 C57BL/6 mice underwent surgery to create defects in the flexor digitorum longus, Achilles, or patellar tendon. Each animal received 1�2 full-thickness, central-width incisional or excisional injuries per limb; at least one tendon per limb remained uninjured. The injuries were distributed such that each tendon type had comparable numbers of uninjured, incisionally-injured, and excisionally-injured specimens. Three weeks after injury, all animals were euthanized and tendons were harvested for mechanical testing. As hypothesized, differences were detected for all three different tendon types at three weeks post-injury. While all models created injuries that produced predictable outcomes, the patellar tendon model was the most consistent in terms of number and size of significant differences in injured tendons compared to native properties, as well as in the overall variance in the data. This finding provides support for its use in fundamental tendon healing studies; however, future work may use any of these models, based on their appropriateness for the specific question under study. PMID:22405494
Beason, David P.; Kuntz, Andrew F.; Hsu, Jason E.; Miller, Kristin S.; Soslowsky, Louis J.
Incidence of Major Tendon Ruptures and Anterior Cruciate Ligament Tears in US Army Soldiers
Background: Although a rare event, the prevalence of major tendon rupture has increased in recent decades. Identification of risk factors is important for prevention purposes.Hypothesis: Race is a risk factor for major tendon ruptures.Study Design: Cohort study (prevalence); Level of evidence, 2.Methods: All patients admitted for surgical management of a rupture of a major tendon at Womack Army Medical Center,
Daniel W. White; Joseph C. Wenke; Dan S. Mosely; Sally B. Mountcastle; Carl J. Basamania
Background: Higher estrogen levels in women seem to play a role regarding an increased ligament and tendon injury rate among women. However, gender differences of tendon microcirculation have not yet been reported.Hypothesis: Female patients suffering Achilles tendinopathy have worse tendon and paratendon microcirculation than symptomatic male patients.Study Design: Cross-sectional study; Level of evidence, 2.Methods: A total of 139 Achilles tendinopathy
Karsten Knobloch; Louisa Schreibmueller; Rupert Meller; Kay H. Busch; Marcus Spies; Peter M. Vogt
Arthroscopic repair of the subscapularis tendon: indications, limits and technical features
Summary The rationale to anatomically repair this tendon is to restore the functional biomechanics of the shoulder. Clinical and imaging assessment are required before undertaking arthroscopy. In this way, associated pathologies of the biceps and labrum may be successfully addressed. The arthroscopic repair of the tendon implies to use suture anchors and reinsert the tendon itself over the footprint. Results after arthroscopy are comparable to those observed after open procedures. PMID:24367783
Osti, Leonardo; Soldati, Francesco; Del Buono, Angelo; Buda, Matteo
Acute Simultaneous Ruptures of the Anterior Cruciate Ligament and Patellar Tendon
Acute simultaneous rupture of the anterior cruciate ligament (ACL) and patellar tendon is a rare injury. We present a case report of a 32-year-old male patient with ruptured ACL and ipsilateral patellar tendon rupture sustained while playing baseball. Surgery was performed on the patellar tendon and the ACL simultaneously. The clinical and radiological outcomes of the treatment were successful. We present this case with a review of the literatures. PMID:24639949
Lee, Gwang Chul; Park, Sung-Hae
Arthroscopic repair of the subscapularis tendon: indications, limits and technical features.
The rationale to anatomically repair this tendon is to restore the functional biomechanics of the shoulder. Clinical and imaging assessment are required before undertaking arthroscopy. In this way, associated pathologies of the biceps and labrum may be successfully addressed. The arthroscopic repair of the tendon implies to use suture anchors and reinsert the tendon itself over the footprint. Results after arthroscopy are comparable to those observed after open procedures. PMID:24367783
Osti, Leonardo; Soldati, Francesco; Buono, Angelo Del; Buda, Matteo
The aim of the present study was to investigate the effects of various decellularization methods on the histological and biomechanical properties of rabbit tendons. In total, six chemical reagents, including 1% t-octyl-phenoxypolyethoxyethanol (Triton-X 100), 0.5% sodium dodecyl sulfate (SDS), 1% tri-n-butyl phosphate (TnBP), 1% Triton-X 100 + 0.5% SDS, 1% TnBP + 0.5% SDS and 1% TnBP + 1% Triton-X 100, were used on rabbit semitendinosus muscles and flexor digitorum tendons for 24 h to remove cells. Hematoxylin and eosin staining was applied for histological observation, while tension testing was used for biomechanical studies. The effects of the various decellularization methods on the histological structure and biomechanical properties of rabbit tendons were evaluated. A group of fresh tendons treated with phosphate-buffered saline served as controls. The various decellularization methods resulted in different effects on the tendons. All the treatment groups exhibited a decrease in tendon biomechanical properties, but no statistically significant differences were observed among the experimental groups. The extensibility of the 1% TnBP-treated group was found to be greater than that of the other groups; however, the difference was not statistically significant. Histologically, the 1% TnBP + 0.5% SDS treatment was shown to have the least impact on the rabbit tendon structure, with good decellularization and no clear cellular remnants observed. The 1% Triton-X 100 + 0.5% SDS treatment had a pronounced effect on the tendon collagen structure and a number of collagen ruptures were observed. Overall, 1% TnBP + 0.5% SDS was found to be the most effective compared with the other treatments, as this treatment preserved the tendon collagen structure while completely removing the cells. Tendons treated with 1% TnBP + 0.5% SDS were histologically similar to normal tendon tissue and biomechanically similar to the tendons in the control group. PMID:25009631
Xing, Shuxing; Liu, Cong; Xu, Bing; Chen, Jianchang; Yin, Dongfeng; Zhang, Chunhao
The aim of the present study was to investigate the effects of various decellularization methods on the histological and biomechanical properties of rabbit tendons. In total, six chemical reagents, including 1% t-octyl-phenoxypolyethoxyethanol (Triton-X 100), 0.5% sodium dodecyl sulfate (SDS), 1% tri-n-butyl phosphate (TnBP), 1% Triton-X 100 + 0.5% SDS, 1% TnBP + 0.5% SDS and 1% TnBP + 1% Triton-X 100, were used on rabbit semitendinosus muscles and flexor digitorum tendons for 24 h to remove cells. Hematoxylin and eosin staining was applied for histological observation, while tension testing was used for biomechanical studies. The effects of the various decellularization methods on the histological structure and biomechanical properties of rabbit tendons were evaluated. A group of fresh tendons treated with phosphate-buffered saline served as controls. The various decellularization methods resulted in different effects on the tendons. All the treatment groups exhibited a decrease in tendon biomechanical properties, but no statistically significant differences were observed among the experimental groups. The extensibility of the 1% TnBP-treated group was found to be greater than that of the other groups; however, the difference was not statistically significant. Histologically, the 1% TnBP + 0.5% SDS treatment was shown to have the least impact on the rabbit tendon structure, with good decellularization and no clear cellular remnants observed. The 1% Triton-X 100 + 0.5% SDS treatment had a pronounced effect on the tendon collagen structure and a number of collagen ruptures were observed. Overall, 1% TnBP + 0.5% SDS was found to be the most effective compared with the other treatments, as this treatment preserved the tendon collagen structure while completely removing the cells. Tendons treated with 1% TnBP + 0.5% SDS were histologically similar to normal tendon tissue and biomechanically similar to the tendons in the control group. PMID:25009631
End-to-End Operative Repair of Achilles Tendon Rupture
We present the long-term results of operative repair in 23 consecutive patients with Achilles tendon ruptures, treated between 1984 and 1991, to evaluate our treat ment method and determine the clinical causes of rupture. Fifty-four percent of ruptures occurred in peo ple in their 30s; 90% occurred during participation in acceleration-deceleration sports. All but three patients were treated within 1
Jeffery J. Soldatis; Donald B. Goodfellow; John H. Wilber
Do Cells Contribute to Tendon and Ligament Biomechanics?
Introduction Acellular scaffolds are increasingly used for the surgical repair of tendon injury and ligament tears. Despite this increased use, very little data exist directly comparing acellular scaffolds and their native counterparts. Such a comparison would help establish the effectiveness of the acellularization procedure of human tissues. Furthermore, such a comparison would help estimate the influence of cells in ligament and tendon stability and give insight into the effects of acellularization on collagen. Material and Methods Eighteen human iliotibial tract samples were obtained from nine body donors. Nine samples were acellularized with sodium dodecyl sulphate (SDS), while nine counterparts from the same donors remained in the native condition. The ends of all samples were plastinated to minimize material slippage. Their water content was adjusted to 69%, using the osmotic stress technique to exclude water content-related alterations of the mechanical properties. Uniaxial tensile testing was performed to obtain the elastic modulus, ultimate stress and maximum strain. The effectiveness of the acellularization procedure was histologically verified by means of a DNA assay. Results The histology samples showed a complete removal of the cells, an extensive, yet incomplete removal of the DNA content and alterations to the extracellular collagen. Tensile properties of the tract samples such as elastic modulus and ultimate stress were unaffected by acellularization with the exception of maximum strain. Discussion The data indicate that cells influence the mechanical properties of ligaments and tendons in vitro to a negligible extent. Moreover, acellularization with SDS alters material properties to a minor extent, indicating that this method provides a biomechanical match in ligament and tendon reconstruction. However, the given protocol insufficiently removes DNA. This may increase the potential for transplant rejection when acellular tract scaffolds are used in soft tissue repair. Further research will help optimize the SDS-protocol for clinical application. PMID:25126746
Hammer, Niels; Huster, Daniel; Fritsch, Sebastian; H�drich, Carsten; Koch, Holger; Schmidt, Peter; Sichting, Freddy; Wagner, Martin Franz-Xaver; Boldt, Andreas
Freeze-thaw cycles enhance decellularization of large tendons.
The use of decellularized tendon tissue as a scaffold for tendon tissue engineering provides great opportunities for future clinical and current research applications. The aim of this study was to assess the effect of repetitive freeze-thaw cycles and two different detergents, t-octyl-phenoxypolyethoxyethanol (Triton X-100) and sodium dodecyl sulfate (SDS), on decellularization effectiveness and cytocompatibility in large tendons. Freshly collected equine superficial and deep digital flexor tendons were subjected to decellularization according to four different protocols (1 and 2: freeze-thaw cycles combined with either Triton X-100 or SDS; 3 and 4: Triton X-100 or SDS). Decellularization effectiveness was assessed based on the reduction of vital cell counts, histologically visible nuclei, and DNA content. Transmission electron microscopy was performed to evaluate cellular and extracellular matrix integrity. Further, cytocompatibility of scaffolds that had been decellularized according to the protocols including freeze-thaw cycles (protocols 1 and 2) was assessed by seeding the scaffolds with superparamagnetic iron oxide labeled mesenchymal stromal cells and monitoring the cells histologically and by magnetic resonance imaging for two weeks. Decellularization was significantly more effective when using the protocols including freeze-thaw cycles, leaving only roughly 1% residual nuclei and 20% residual DNA, whereas samples that had not undergone additional freeze-thaw cycles contained roughly 20% residual nuclei and 40% residual DNA. No morphological extracellular matrix alterations due to decellularization could be observed. Scaffolds prepared by both protocols including freeze-thaw cycles were cytocompatible, but the cell distribution into the scaffold tended to be better in scaffolds that had been decellularized using freeze-thaw cycles combined with Triton X-100 instead of SDS. PMID:23879725
Burk, Janina; Erbe, Ina; Berner, Dagmar; Kacza, Johannes; Kasper, Cornelia; Pfeiffer, Bastian; Winter, Karsten; Brehm, Walter
[Management of zone 1�flexor digitorum profundus tendon injuries].
Flexor tendons repair in zone 1�is classically considered providing good results with an overall satisfactory finger function. However, the objective functional results after surgical repair of flexor digitorum profundus are sometimes disappointing. The authors describe the different surgical repair techniques available to the operator from so-called "traditional" sutures to newer methods of internal fixation using miniaturized anchor sutures. The management of postoperative procedures, that of failures and old cases are reported. PMID:24837520
Forli, A; Corcella, D; Semere, A; Mesquida, V; Moutet, F
Effect of calendula officinalis cream on achilles tendon healing.
In recent years, the scientific community has undertaken research on plant extracts, searching for compounds with pharmacological activities that can be used in diverse fields of medicine. Calendula officinalis L. is known to have antioxidant, anti-inflammatory, antibacterial, and wound healing properties when used to treat skin burns. Therefore, the purpose of this study was to analyze the effects of C. officinalis on the initial phase of Achilles tendon healing. Wistar rats were separated in three groups: Calendula (Cal)-rats with a transected tendon were treated with topical applications of C. officinalis cream and then euthanized 7 days after injury; Control (C)-rats were treated with only vehicle after transection; and Normal (N)-rats without tenotomy. Higher concentrations of hydroxyproline (an indicator of total collagen) and non-collagenous proteins were observed in the Cal group in relation to the C group. Zymography showed no difference in the amount of the isoforms of metalloproteinase-2 and of metalloproteinase-9, between C and Cal groups. Polarization microscopy images analysis showed that the Cal group presented a slightly higher birefringence compared with the C group. In sections of tendons stained with toluidine blue, the transected groups presented higher metachromasy as compared with the N group. Immunocytochemistry analysis for chondroitin-6-sulfate showed no difference between the C and Cal groups. In conclusion, the topical application of C. officinalis after tendon transection increases the concentrations of collagen and non-collagenous proteins, as well as the collagen organization in the initial phase of healing. Anat Rec, 298:428-435, 2015. � 2014 Wiley Periodicals, Inc. PMID:25266273
Aro, A A; Perez, M O; Vieira, C P; Esquisatto, M A M; Rodrigues, R A F; Gomes, L; Pimentel, E R
Achilles tendon rupture - treatment and complications: A systematic review.
Achilles tendon rupture is a frequent injury with an increasing incidence. Until now, there is no consensus regarding optimal treatment. The aim of this review was to illuminate and summarize randomized controlled trials comparing surgical and non-surgical treatment of Achilles tendon ruptures during the last 10 years. Seven articles were found and they were all acceptable according to international quality assessment guidelines. Primary outcomes were re-ruptures, other complications, and functional outcomes. There was no significant difference in re-ruptures between the two treatments, but a tendency to favoring surgical treatment. Further, one study found an increased risk of soft-tissue-related complications after surgery. Patient satisfaction and time to return to work were significantly different in favor of surgery in one study, and there was also better functional outcome after surgery in some studies. These seven studies indicate that surgical patients have a faster rehabilitation. However, the differences between surgical and non-surgical treatment appear to be subtle and it could mean that rehabilitation is more important, rather than the actual initial treatment. Therefore, further studies will be needed in regard to understanding the interplay between acute surgical or non-surgical treatment, and the rehabilitation regimen for the overall outcome after Achilles tendon ruptures. PMID:24650079
Holm, C; Kjaer, M; Eliasson, P
Hamstring tendon graft for anterior cruciate ligament reconstruction.
In an age of increasing emphasis on sports, the most common contact injury of the lower extremity is anterior cruciate ligament (ACL) rupture. The classic history of an ACL injury is a sudden twisting of the knee accompanied by a popping or snapping sound. The patient usually complains of a feeling of hesitation, instability, or giving way of the knee. By the end of the day, the patient's knee will be swollen and unstable. There are many ways that the ACL can rupture, but a common method is a contact injury in which a valgus force is applied to the flexed, rotated externally knee. This can produce tears to the ACL, medial collateral ligament, and menisci. Noncontact injuries, such as those incurred while skiing or jumping, occur when the knee is extended and the tibia is internally rotated on the femur. There are several methods of repairing a ruptured ACL, such as using an allograft or autograft of the patella tendon or a hamstring tendon graft for the repair. This article focuses on the use of a hamstring tendon graft for ACL reconstruction and how to care for patients undergoing this procedure. PMID:12382466
Boni, Deborah M; Herriott, George E
The effect of the Achilles tendon on trabecular structure in the primate calcaneus.
Humans possess the longest Achilles tendon relative to total muscle length of any primate, an anatomy that is beneficial for bipedal locomotion. Reconstructing the evolutionary history of the Achilles tendon has been challenging, in part because soft tissue does not fossilize. The only skeletal evidence for Achilles tendon anatomy in extinct taxa is the insertion site on the calcaneal tuber, which is rarely preserved in the fossil record and, when present, is equivocal for reconstructing tendon morphology. In this study, we used high-resolution three-dimensional microcomputed tomography (micro-CT) to quantify the microstructure of the trabecular bone underlying the Achilles tendon insertion site in baboons, gibbons, chimpanzees, and humans to test the hypothesis that trabecular orientation differs among primates with different tendon morphologies. Surprisingly, despite their very different Achilles tendon lengths, we were unable to find differences between the trabecular properties of chimpanzee and human calcanei in this specific region. There were regional differences within the calcaneus in the degree of anisotropy (DA) in both chimpanzees and humans, though the patterns were similar between the two species (higher DA inferiorly in the calcaneal tuber). Our results suggest that while trabecular bone within the calcaneus varies, it does not respond to the variation of Achilles tendon morphology across taxa in the way we hypothesized. These results imply that internal bone architecture may not be informative for reconstructing Achilles tendon anatomy in early hominins. PMID:23821323
Kuo, Sharon; Desilva, Jeremy M; Devlin, Maureen J; McDonald, Gabriel; Morgan, Elise F
Objective Patellar tendon injury, defined by tendon abnormality (TA) on imaging and by pain, is common among volleyball players, but little is known about change in this injury over a volleyball season. Increased activity in the season compared with the off season may result in the development of TA and/or pain. This study investigated the behaviour of TA and pain over a competitive volleyball season. Methods Tendon abnormality and pain were measured in 101 volleyball players at the beginning and end of a season. Pain was measured with the single leg decline squat test, which loads the patellar tendon, and TA was detected with ultrasound imaging. Hours of weekly activity were measured and compared during the season and the off season. The proportion of tendons that underwent development and resolution in TA and/or pain over the season was investigated. Results Hours of weekly activity was greater during the season than in the off season. Most of the tendons investigated (66.3%) did not undergo a change in TA or pain over the season. Tendon abnormality and/or pain developed in 16.6% of tendons and resolved in 11.2%. Conclusions The tendons of volleyball players respond variably to the increased load over the season. Change in TA and pain does not appear to be entirely dependent upon load. PMID:16505088
Malliaras, P; Cook, J; Ptasznik, R; Thomas, S
Achilles tendon shape and echogenicity on ultrasound among active badminton players.
The relationship between Achilles tendon ultrasound abnormalities, including a spindle shape and heterogeneous echogenicity, is unclear. This study investigated the relationship between these abnormalities, tendon thickness, Doppler flow and pain. Sixty-one badminton players (122 tendons, 36 men, and 25 women) were recruited. Achilles tendon thickness, shape (spindle, parallel), echogenicity (heterogeneous, homogeneous) and Doppler flow (present or absent) were measured bilaterally with ultrasound. Achilles tendon pain (during or after activity over the last week) and pain and function [Victorian Institute of Sport Achilles Assessment (VISA-A)] were measured. Sixty-eight (56%) tendons were parallel with homogeneous echogenicity (normal), 22 (18%) were spindle shaped with homogeneous echogenicity, 16 (13%) were parallel with heterogeneous echogenicity and 16 (13%) were spindle shaped with heterogeneous echogenicity. Spindle shape was associated with self-reported pain (P<0.05). Heterogeneous echogenicity was associated with lower VISA-A scores than normal tendon (P<0.05). There was an ordinal relationship between normal tendon, parallel and heterogeneous and spindle shaped and heterogeneous tendons with regard to increasing thickness and likelihood of Doppler flow. Heterogeneous echogenicity with a parallel shape may be a physiological phase and may develop into heterogeneous echogenicity with a spindle shape that is more likely to be pathological. PMID:20561268
Malliaras, P; Voss, C; Garau, G; Richards, P; Maffulli, N
Zone 2 flexor tendon injuries: Venturing into the no man's land
Flexor tendon injuries are seen commonly yet the management protocols are still widely debated. The advances in suture techniques, better understanding of the tendon morphology and its biomechanics have resulted in better outcomes. There has been a trend toward the active mobilization protocols with development of multistrand core suture techniques. Zone 2 injuries remain an enigma for the hand surgeons even today but the outcome results have definitely improved. Biomolecular modulation of tendon repair and tissue engineering are now the upcoming fields for future research. This review article focuses on the current concepts in the management of flexor tendon injuries in zone 2. PMID:23325961
Kotwal, Prakash P; Ansari, Mohammed Tahir
Heterotopic tendon mineralization (ossification or calcification), which may be a feature of tendinopathy or which may develop following surgical trauma (repair or graft harvest), has not received much attention. The purpose of this article is to review the prevalence, mechanisms and consequences of heterotopic tendon mineralization and to identify the gaps in our current understanding. We focus on endochondral heterotopic ossification and draw on knowledge of the mechanisms of this process in other tissues and conditions. Finally, we introduce a novel murine Achilles tendon needle injury model, which will enable us to further study the mechanisms and biomechanical consequences of tendon mineralization. PMID:22974213
O'Brien, Etienne J O; Frank, Cyril B; Shrive, Nigel G; Hallgr�msson, Benedikt; Hart, David A
Experimental study of the effects of helium-neon laser radiation on repair of injured tendon
NASA Astrophysics Data System (ADS)
Despite extensive research into the biology of tendon healing, predictably restoring normal function to a digit after a flexor tendon laceration remains one of the most difficult problems facing the hand surgeon. The challenge of simultaneously achieving tendon healing while minimizing the peritendinous scar formation, which limits tendon gliding, has captured the attention of investigators for many years. It has been said that low-power density helium-neon laser radiation had effects on anti-inflammation, detumescence, progressive wound healing, and reducing intestinal adhesions. This experimental study aims at whether helium-neon laser can reduce injured tendon adhesions and improve functional recovery of the injured tendon. Fifty white Leghorn hens were used. Ten were randomly assigned as a normal control group, the other forty were used in the operation. After anesthetizing them with Amytal, a half of the profundus tendons of the second and third foretoes on both sides of the feet were cut. Postoperatively, the hens moved freely in the cages. One side of the toes operated on were randomly chosen as a treatment group, the other side served as an untreated control group. The injured tendon toes in the treatment group were irradiated for twenty minutes daily with a fiber light needle of helium-neon laser therapeutic apparatus (wavelength, 6328 angstroms) at a constant power density of 12.74 mW/cm2, the first exposure taking place 24 hours after the operation. The longest course of treatment was 3 weeks. The control group was not irradiated. At 3 days, 1, 2, 3, and 5 weeks after surgery, 8 hens were sacrificed and their tendons were examined. The experimental results: (1) active, passive flexion and tendon gliding functional recovery were significantly better in the treatment group (p < 0.01); (2) width and thickness of the tendon at the cut site were significantly smaller in the treatment group (p < 0.01); (3) degrees of tendon adhesions were significantly lighter in the treatment group (p < 0.05). The experimental results demonstrate helium-neon laser radiation had significant effects on anti-inflammation, detumescence, progressive hematoma absorbing, inhibiting the tendon extrinsic healing, reducing tendon adhesions, improving the tendon intrinsic healing, i.e., stimulating epitenon and endotenon cells proliferation and migrating into the gap, stimulating collagen synthesis in the tendon gap, and enhancing the late remodeling of fibrous peritendonous adhesion.
Xu, Yong-Qing; Li, Zhu-Yi; Weng, Long-Jiang; An, Mei; Li, Kai-Yun; Chen, Shao-Rong; Wang, Jian-Xin; Lu, Yu
Lack of tissue renewal in human adult Achilles tendon is revealed by nuclear bomb (14)C.
Tendons are often injured and heal poorly. Whether this is caused by a slow tissue turnover is unknown, since existing data provide diverging estimates of tendon protein half-life that range from 2 mo to 200 yr. With the purpose of determining life-long turnover of human tendon tissue, we used the (14)C bomb-pulse method. This method takes advantage of the dramatic increase in atmospheric levels of (14)C, produced by nuclear bomb tests in 1955-1963, which is reflected in all living organisms. Levels of (14)C were measured in 28 forensic samples of Achilles tendon core and 4 skeletal muscle samples (donor birth years 1945-1983) with accelerator mass spectrometry (AMS) and compared to known atmospheric levels to estimate tissue turnover. We found that Achilles tendon tissue retained levels of (14)C corresponding to atmospheric levels several decades before tissue sampling, demonstrating a very limited tissue turnover. The tendon concentrations of (14)C approximately reflected the atmospheric levels present during the first 17 yr of life, indicating that the tendon core is formed during height growth and is essentially not renewed thereafter. In contrast, (14)C levels in muscle indicated continuous turnover. Our observation provides a fundamental premise for understanding tendon function and pathology, and likely explains the poor regenerative capacity of tendon tissue. PMID:23401563
Heinemeier, Katja Maria; Schjerling, Peter; Heinemeier, Jan; Magnusson, Stig Peter; Kjaer, Michael
Tendon proper- and peritenon-derived progenitor cells have unique tenogenic properties
Introduction Multipotent progenitor populations exist within the tendon proper and peritenon of the Achilles tendon. Progenitor populations derived from the tendon proper and peritenon are enriched with distinct cell types that are distinguished by expression of markers of tendon and vascular or pericyte origins, respectively. The objective of this study was to discern the unique tenogenic properties of tendon proper- and peritenon-derived progenitors within an in vitro model. We hypothesized that progenitors from each region contribute differently to tendon formation; thus, when incorporated into a regenerative model, progenitors from each region will respond uniquely. Moreover, we hypothesized that cell populations like progenitors were capable of stimulating tenogenic differentiation, so we generated conditioned media from these cell types to analyze their stimulatory potentials. Methods Isolated progenitors were seeded within fibrinogen/thrombin gel-based constructs with or without supplementation with recombinant growth/differentiation factor-5 (GDF5). Early and late in culture, gene expression of differentiation markers and matrix assembly genes was analyzed. Tendon construct ultrastructure was also compared after 45�days. Moreover, conditioned media from tendon proper-derived progenitors, peritenon-derived progenitors, or tenocytes was applied to each of the three cell types to determine paracrine stimulatory effects of the factors secreted from each of the respective cell types. Results The cell orientation, extracellular domain and fibril organization of constructs were comparable to embryonic tendon. The tendon proper-derived progenitors produced a more tendon-like construct than the peritenon-derived progenitors. Seeded tendon proper-derived progenitors expressed greater levels of tenogenic markers and matrix assembly genes, relative to peritenon-derived progenitors. However, GDF5 supplementation improved expression of matrix assembly genes in peritenon progenitors and structurally led to increased mean fibril diameters. It also was found that peritenon-derived progenitors secrete factor(s) stimulatory to tenocytes and tendon proper progenitors. Conclusions Data demonstrate that, relative to peritenon-derived progenitors, tendon proper progenitors have greater potential for forming functional tendon-like tissue. Furthermore, factors secreted by peritenon-derived progenitors suggest a trophic role for this cell type as well. Thus, these findings highlight the synergistic potential of including these progenitor populations in restorative tendon engineering strategies. PMID:25005797
Spontaneous Rupture of the Extensor Pollicis Longus Tendon due to Unusual Etiology
Background: The etiology of spontaneous rupture of the extensor pollicis longus tendon includes systemic or local steroid injections, wrist fracture, tenosynovitis, synovitis, rheumatoid arthritis, and repetitive wrist motions. Case Report: We encountered a case of extensor pollicis longus tendon rupture with an unusual etiology, cow milking. In this case, transfer of the extensor indicis proprius tendon was performed successfully. At 1 year after surgery, extension of the thumb was sufficient. Conclusion: It appears that patients with occupations involving repetitive motions are at a high risk of closed tendon ruptures. PMID:25207178
Ta?, S�leyman; Balta, Serkan; Benlier, Erol
Tendons connect muscles to bones, and serve as the transmitters of force that allow all the movements of the body. Tenocytes are the basic cellular units of tendons, and produce the collagens that form the hierarchical fiber system of the tendon. Tendon injuries are common, and difficult to repair, particularly in the case of the insertion of tendon into bone. Successful attempts at cell-based repair therapies will require an understanding of the normal development of tendon tissues, including their differentiated regions such as the fibrous mid-section and fibrocartilaginous insertion site. Many genes are known to be involved in the formation of tendon. However, their functional roles in tendon development have not been fully characterized. Tissue engineers have attempted to generate functional tendon tissue in vitro. However, a lack of knowledge of normal tendon development has hampered these efforts. Here we review studies focusing on the developmental mechanisms of tendon development, and discuss the potential applications of a molecular understanding of tendon development to the treatment of tendon injuries. PMID:21314435
Liu, Chia-Feng; Aschbacher-Smith, Lindsey; Barthelery, Nicolas J.; Dyment, Nathaniel; Butler, David
A Novel Arthroscopic Inside-Out Repair Technique for PASTA�Lesions
There is no current consensus in the literature on the optimal technique for surgical treatment of partial articular-sided supraspinatus tendon avulsion (PASTA) lesions, although most techniques described to date require takedown of the partially torn tendon or passage of an anchor through the already damaged tendon. We describe a novel inside-out repair technique for partial articular surface supraspinatus tears that does not require further disruption of the partially torn tendon by passage of an anchor. PMID:25473607
Caldwell, Lindsey S.; Cooper, Anna R.; Elfar, John C.
A Novel Arthroscopic Inside-Out Repair Technique for PASTA�Lesions.
There is no current consensus in the literature on the optimal technique for surgical treatment of partial articular-sided supraspinatus tendon avulsion (PASTA) lesions, although most techniques described to date require takedown of the partially torn tendon or passage of an anchor through the already damaged tendon. We describe a novel inside-out repair technique for partial articular surface supraspinatus tears that does not require further disruption of the partially torn tendon by passage of an anchor. PMID:25473607
Caldwell, Lindsey S; Cooper, Anna R; Elfar, John C
Elastic properties of human Achilles tendon are correlated to muscle strength.
The purpose of this study was to investigate whether the mechanical properties of the Achilles tendon were correlated to muscle strength in the triceps surae in humans. Twenty-four men and twelve women exerted maximal voluntary isometric plantar flexion (MVIP) torque. The elongation (DeltaX) and strain of the Achilles tendon (epsilon), the proximal part of which is the composite of the gastrocnemius tendon and the soleus aponeurosis, at MVIP were determined from the displacement of the distal myotendinous junction of the medial gastrocnemius using ultrasonography. The Achilles tendon force at MVIP (F) was calculated from the MVIP torque and the Achilles tendon moment arm. There were no significant differences in either the F-DeltaX or F-epsilon relationships between men and women. DeltaX and epsilon were 9.8 +/- 2.6 mm and 5.3 +/- 1.6%, respectively, and were positively correlated to F (r = 0.39, P < 0.05; r = 0.39, P < 0.05), which meant that subjects with greater muscle strength could store more elastic energy in the tendon. The regression y-intercepts for the F-DeltaX (P < 0.01) and F-epsilon (P < 0.05) relationship were significantly positive. These results might indicate that the Achilles tendon was stiffer in subjects with greater muscle strength, which may play a role in reducing the probability of tendon strain injuries. It was suggested that the Achilles tendon of subjects with greater muscle strength did not impair the potential for storing elastic energy in tendons and may be able to deliver the greater force supplied from a stronger muscle more efficiently. Furthermore, the difference in the Achilles tendon mechanical properties between men and women seemed to be correlated to the difference in muscle strength rather than gender. PMID:15790689
Muraoka, Tetsuro; Muramatsu, Tadashi; Fukunaga, Tetsuo; Kanehisa, Hiroaki
The paratenon contributes to scleraxis-expressing cells during patellar tendon healing.
The origin of cells that contribute to tendon healing, specifically extrinsic epitenon/paratenon cells vs. internal tendon fibroblasts, is still debated. The purpose of this study is to determine the location and phenotype of cells that contribute to healing of a central patellar tendon defect injury in the mouse. Normal adult patellar tendon consists of scleraxis-expressing (Scx) tendon fibroblasts situated among aligned collagen fibrils. The tendon body is surrounded by paratenon, which consists of a thin layer of cells that do not express Scx and collagen fibers oriented circumferentially around the tendon. At 3 days following injury, the paratenon thickens as cells within the paratenon proliferate and begin producing tenascin-C and fibromodulin. These cells migrate toward the defect site and express scleraxis and smooth muscle actin alpha by day 7. The thickened paratenon tissue eventually bridges the tendon defect by day 14. Similarly, cells within the periphery of the adjacent tendon struts express these markers and become disorganized. Cells within the defect region show increased expression of fibrillar collagens (Col1a1 and Col3a1) but decreased expression of tenogenic transcription factors (scleraxis and mohawk homeobox) and collagen assembly genes (fibromodulin and decorin). By contrast, early growth response 1 and 2 are upregulated in these tissues along with tenascin-C. These results suggest that paratenon cells, which normally do not express Scx, respond to injury by turning on Scx and assembling matrix to bridge the defect. Future studies are needed to determine the signaling pathways that drive these cells and whether they are capable of producing a functional tendon matrix. Understanding this process may guide tissue engineering strategies in the future by stimulating these cells to improve tendon repair. PMID:23555841
Dyment, Nathaniel A; Liu, Chia-Feng; Kazemi, Namdar; Aschbacher-Smith, Lindsey E; Kenter, Keith; Breidenbach, Andrew P; Shearn, Jason T; Wylie, Christopher; Rowe, David W; Butler, David L
The Paratenon Contributes to Scleraxis-Expressing Cells during Patellar Tendon Healing
The origin of cells that contribute to tendon healing, specifically extrinsic epitenon/paratenon cells vs. internal tendon fibroblasts, is still debated. The purpose of this study is to determine the location and phenotype of cells that contribute to healing of a central patellar tendon defect injury in the mouse. Normal adult patellar tendon consists of scleraxis-expressing (Scx) tendon fibroblasts situated among aligned collagen fibrils. The tendon body is surrounded by paratenon, which consists of a thin layer of cells that do not express Scx and collagen fibers oriented circumferentially around the tendon. At 3 days following injury, the paratenon thickens as cells within the paratenon proliferate and begin producing tenascin-C and fibromodulin. These cells migrate toward the defect site and express scleraxis and smooth muscle actin alpha by day 7. The thickened paratenon tissue eventually bridges the tendon defect by day 14. Similarly, cells within the periphery of the adjacent tendon struts express these markers and become disorganized. Cells within the defect region show increased expression of fibrillar collagens (Col1a1 and Col3a1) but decreased expression of tenogenic transcription factors (scleraxis and mohawk homeobox) and collagen assembly genes (fibromodulin and decorin). By contrast, early growth response 1 and 2 are upregulated in these tissues along with tenascin-C. These results suggest that paratenon cells, which normally do not express Scx, respond to injury by turning on Scx and assembling matrix to bridge the defect. Future studies are needed to determine the signaling pathways that drive these cells and whether they are capable of producing a functional tendon matrix. Understanding this process may guide tissue engineering strategies in the future by stimulating these cells to improve tendon repair. PMID:23555841
Dyment, Nathaniel A.; Liu, Chia-Feng; Kazemi, Namdar; Aschbacher-Smith, Lindsey E.; Kenter, Keith; Breidenbach, Andrew P.; Shearn, Jason T.; Wylie, Christopher; Rowe, David W.; Butler, David L.
An experimental study of low-level laser therapy in rat Achilles tendon injury.
The aim of this controlled animal study was to investigate the effect of low-level laser therapy (LLLT) administered 30 min after injury to the Achilles tendon. The study animals comprised 16 Sprague Dawley male rats divided in two groups. The right Achilles tendons were injured by blunt trauma using a mini guillotine, and were treated with LLLT or placebo LLLT 30 min later. The injury and LLLT procedures were then repeated 15 hours later on the same tendon. One group received active LLLT (? = 904 nm, 60 mW mean output power, 0.158 W/cm(2) for 50 s, energy 3 J) and the other group received placebo LLLT 23 hours after LLLT. Ultrasonographic images were taken to measure the thickness of the right and left Achilles tendons. Animals were then killed, and all Achilles tendons were tested for ultimate tensile strength (UTS). All analyses were performed by blinded observers. There was a significant increase in tendon thickness in the active LLLT group when compared with the placebo group (p < 0.05) and there were no significant differences between the placebo and uninjured left tendons. There were no significant differences in UTS between laser-treated, placebo-treated and uninjured tendons. Laser irradiation of the Achilles tendon at 0.158 W/cm(2) for 50 s (3 J) administered within the first 30 min after blunt trauma, and repeated after 15 h, appears to lead to edema of the tendon measured 23 hours after LLLT. The guillotine blunt trauma model seems suitable for inflicting tendon injury and measuring the effects of treatment on edema by ultrasonography and UTS. More studies are needed to further refine this model. PMID:21547473
Joensen, Jon; Gjerdet, Nils Roar; Hummelsund, Steinar; Iversen, Vegard; Lopes-Martins, Rodrigo Alvaro B; Bjordal, Jan Magnus
Tendons have complex mechanical behaviors that are viscoelastic, nonlinear, and anisotropic. It is widely held that these behaviors are provided for by the tissue's composition and structure. However, little data are available to quantify such structure�function relationships. This study quantified tendon mechanical behaviors, including viscoelasticity and nonlinearity, for groups of mice that were genetically engineered for altered extracellular matrix proteins.
Dawn M. Elliott; Paul S. Robinson; Jonathan A. Gimbel; Joseph J. Sarver; Joseph A. Abboud; Renato V. Iozzo; Louis J. Soslowsky
Comparison of therapeutic ultrasound and exercises for augmenting tendon healing in rats
We compared therapeutic ultrasound (US) and exercises on Achilles tendon healing in 49 mature male rats. The medial Achilles tendon of the right leg was transected and the rats were divided into five groups: 1. control (n = 9), 2. 1 W\\/cm2 US (n = 9), 3. 2 W\\/cm� US (n = 10), 4. running (n = 11) and 5.
G. Y. F. Ng; C. O. Y. Ng; E. K. N. See
Summary: Recently it has been shown that anatomic tibial graft fixation in anterior cruciate ligament (ACL) reconstruction is preferable in order to increase isometry and knee stability. To facilitate anatomic patellar tendon graft fixation, customized graft length shortening is necessary. The purpose of this study was to compare the initial fixation strength of four different shortened patellar tendon grafts including
Reinhard F. G. Hoffmann; Ricarda Peine; Hermann J. Bail; Norbert P. S�dkamp; Andreas Weiler
INTRODUCTION: In this study, we aimed to investigate ultrasonographic (US) changes suggestive of gouty arthritis in the hyaline cartilage, joints and tendons from asymptomatic individuals with hyperuricemia. METHODS: We conducted a cross-sectional, controlled study including US examinations of the knees and first metatarsal-phalangeal joints (first MTPJs), as well as of the tendons and enthesis of the lower limbs. Differences were
Carlos Pineda; Luis M Amezcua-Guerra; Carla Solano; Pedro Rodriguez-Henr�quez; Cristina Hern�ndez-D�az; Angelica Vargas; Fritz Hofmann; Marwin Guti�rrez
OBJECTIVE To find the nature of tendon involvement in chronic kidney disease (CKD) patients on regular hemodialysis (RD), and its relationship to parathyroid hormone (PTH) level using ultrasonography (US). METHOD A total of 50 CKD patients on RD subjected to musculoskeletal examination of knee and ankle, laboratory evaluation, and US of quadriceps tendon and Achilles tendon were involved. RESULTS Ankle joint tenderness was the most frequent sign on examination. US of the Achilles tendons showed tenderness during probing in 44% patients, calcific deposition in 24% patients, abnormal peritendon tissue in 20% patients, and abnormal anteroposterior (A-P) middle and distal one-third thicknesses of the Achilles tendon in 20% and 18% patients, respectively. PTH positively correlated with the duration of dialysis, serum phosphorus level, presence of calcific deposit, and increased thickness of the Achilles tendon. CONCLUSION The most common ultrasonographic finding in CKD patients on RD was Achilles tendon tenderness during probing. PTH level positively correlated with the duration of dialysis, presence of calcific deposit, and increased thickness of Achilles tendon. PMID:25674023
Hussein, Dahlia A; El-Azizi, Noran O; Abdel Meged, Ali H; Al-Hoseiny, Sameh A; Hamada, Abdelhady M; Sabry, Moshira H
Chronic Achilles tendon pain treated with eccentric calf-muscle training
Injuries involving the Achilles tendon and manifested as chronic tendon pain are common, especially among recreational athletes. In a pilot study on a small group of patients with chronic painful mid-portion Achilles tendinosis, eccentric calf-muscle training was shown to give good clinical results. The aim of this prospective study was to investigate if the previously achieved good clinical results could
Martin Fahlstr�m; Per Jonsson; Ronny Lorentzon; H�kan Alfredson
We describe by routine histology and by immunohistochemistry three phenotypically and developmentally distinct fibrocartilages associated with the Achilles tendon of the rat. All the fibrocartilages develop after birth and show significant age-related changes in the composition of their extracellular matrix. Attachment-zone fibrocartilage occurs at the insertion of the tendon on the calcaneus. It derives from the cartilage rudiment of the
A. Rufai; M. Benjamin; J. R. Ralphs
Immediate Free Ankle Motion After Surgical Repair of Acute Achilles Tendon Ruptures
We prospectively studied 17 consecutively treated pa tients (15 men and 2 women) who had surgically treated subcutaneous, complete and acute Achilles tendon rup tures. The patients underwent a new postoperative regi men that allowed free ankle motion in a patellar tendon bearing plaster cast with a protecting frame under the foot making weightbearing possible immediately after surgery. Evaluation was
Sven-A. S�lveborn; Anders Moberg
[Successive ruptures of patellar and Achilles tendons. Anabolic steroids in competitive sports].
Derivatives of testosterone or of 19-nor-testosterone are used as anabolics for the purpose of improving performance although the effect of anabolics is known still to be under discussion. The use of anabolic steroids continues among competitive athletes despite increased controls and increasingly frequent dramatic incidents connected with them. Whereas metabolic dysfunction during anabolic use is well documented, ruptures of the large tendons are rarely reported. Within 18 months, a 29-year-old professional footballer needed surgery for rupture of the patellar tendon and of both Achilles tendons. Carefully directed questioning elicited confirmation that he had taken different anabolic steroids regularly for 3 years with the intention of improving his strength. After each operation anabolic steroids were taken again at a high dosage during early convalescence and training. Minimally invasive surgery and open suturing techniques led to complete union of the Achilles tendons in good time. Training and anabolic use (metenolon 300 mg per week) started early after suturing of the patellar tendon including bone tunnels culminated in histologically confirmed rerupture after 8 weeks. After a ligament reconstruction with a semitendinosus tendon graft with subsequent infection, the tendon and reserve traction apparatus were lost. Repeated warnings of impaired healing if anabolic use was continued had been given without success. In view of the high number of unrecorded cases in competitive and athletic sports, we can assume that the use of anabolic steroids is also of quantitative relevance in the operative treatment of tendon ruptures. PMID:17701152
Isenberg, J; Prokop, A; Skouras, E
Posterior tibial tendon entrapment within an intact ankle mortise: a case report.
The present case report demonstrates a rare finding associated with irreducible ankle fracture dislocations. To our knowledge, posterior tibial tendon entrapment with an intact ankle mortise has not yet been documented in published studies. In the case of our patient, a high-energy, 12-ft fall resulted in a comminuted intra-articular fracture of the medial malleolus, confirmed by the initial radiographs. Preoperative magnetic resonance imaging showed the Achilles tendon to be ruptured and the posterior tibial tendon to be both displaced and entrapped between the medial malleolar fracture fragments, preventing initial closed reduction. At operative repair for the ruptured Achilles tendon and the medial malleolus fracture, the posterior tibial tendon was removed from the fracture site and was found to be intact with no evidence of laceration or rupture. The tendon was returned back to its anatomic position, and the tendon sheath was reapproximated. Although uncommon, it is important that entrapment of the posterior tibial tendon be considered in cases of irreducible ankle fracture. This injury type can be addressed during open reduction internal fixation to achieve reduction. PMID:25441277
Hunter, Allison M; Bowlin, Christopher
Ultrasound Stimulation of Type I Collagen and Type III Collagen Expression of Tendon Cells
NASA Astrophysics Data System (ADS)
This study was designed to determine the effect of ultrasound on tendon cells intrinsic to rat Achilles tendon plated on collagen-coated dishes. Furthermore, the in vitro effect of ultrasound on type I collagen and type III collage expression of tendon cells was investigated. Cultured tendon cells were treated with ultrasound at a frequency of 1.0 MHz, either pulsed (duty factor: 20%) or continuous mode with the intensity of 1.0 W/cm2 for 5 minutes. The expression of type I collagen and type III collagen of tendon cells was evaluated by immunocytochemistry 24 hours after ultrasound treatment. The results revealed that tendon cells cultured on dishes without collagen coating would lyse and detach from the dish after ultrasound exposure. However, cells cultured on collagen-coated dishes proliferate actively. Immunocytochemical staining revealed that ultrasound treated tendon cells stained more strongly for type I collagen and type III collagen than control cells. In conclusion, a collagen-coated dish is essential to prevent cell lysis and detachment from the dish after ultrasound exposure. Furthermore, either continuous or pulsed ultrasound could stimulate the expression of type I collagen and type III collagen by tendon cells.
Chen, Huang-Chung; Tsai, Wen-Chung; Tang, Chu-Wen; Pang, Jong-Hwei S.
Influence of nanofibers on growth and gene expression of human tendon derived fibroblast
BACKGROUND: Rotator cuff tears are a common and frequent lesion especially in older patients. The mechanisms of tendon repair are not fully understood. Common therapy options for tendon repair include mini-open or arthroscopic surgery. The use of growth factors in experimental studies is mentioned in the literature. Nanofiber scaffolds, which provide several criteria for the healing process, might be a
Christina Theisen; Susanne Fuchs-Winkelmann; Karola Knappstein; Turgay Efe; Jan Schmitt; Juergen RJ Paletta; Markus D Schofer
Human Leg Model Predicts Ankle Muscle-Tendon Morphology, State, Roles and Energetics in Walking
Human Leg Model Predicts Ankle Muscle-Tendon Morphology, State, Roles and Energetics in Walking to be established. Here we develop a computational framework to address how the ankle joint actuation problem-tendon morphology and neural activations enable a metabolically optimal realization of biological ankle mechanics
Herr, Hugh
Structure and Functional Evaluation of Tendon�Skeletal Muscle Constructs Engineered in Vitro
During muscle contraction, the integrity of the myotendinous junction (MTJ) is important for the transmission of force from muscle to tendon. We evaluated the contractile and structural characteristics of 3-dimensional (3-D) skeletal muscle constructs co-cultured with engineered self-organized tendon constructs (n = 4), or segments of adult (n = 4) or fetal (n = 5) rat-tail tendon. We hypothesized that the co-culture of tendon and muscle would produce constructs with viable muscle�tendon interfaces that remain intact during generation of force. Construct diameter (?m) and maximum isometric force (?N) were measured, and specific force (kPa) was determined. After measure of force, constructs were loaded at a constant strain rate until failure and surface strains were recorded optically across the tendon, the muscle and the interface and used to determine the tangent modulus (passive stiffness) of the construct. Frozen samples were used for Trichrome Masson staining and immunofluorescent analysis of the MTJ-specific protein paxillin. No differences were observed between the groups with respect to diameter, maximum force, or specific force. The MTJ was robust and withstood tensile loading beyond the physiological strain range. The majority of the constructs failed in the muscle region. At the MTJ, there is an increase in the expression and localization of paxillin. In conclusion, using 3 sources of tendon tissue, we successfully engineered 3-D muscle�tendon constructs with functionally viable MTJ, characterized by structural features and protein expression patterns resembling neonatal MTJs in vivo. PMID:17518629
The authors conducted a systematic review to assess the effectiveness of extracorporeal shock wave therapy (ESWT) for the treatment of calcific and noncalcific tendonitis of the rotator cuff. Conservative treatment for rotator cuff tendonitis includes physiotherapy, nonsteroidal antiinflammatory drugs, and corticosteroid injections. If symptoms persist with conservative treatment, surgery is often considered. Extracorporeal shock wave therapy has been suggested as
Dorcas Beaton
Positioning Techniques to Reduce the Occurrence of DeQuervain's Tendonitis in Nursing Mothers
ERIC Educational Resources Information Center
DeQuervain's tendonitis is an inflammation of two tendons: the extensor pollicis brevis and the abductor pollicis longus as they cross in the first dorsal compartment of the wrist. Symptoms include pain, swelling along the radial aspect of the wrist, and a decrease in thumb motion. A positive Finkelstein's test at examination is seen. Frequently�
Virzi, Alison
Efficacy of a mesenchymal stem cell loaded surgical mesh for tendon repair in rats
Objectives The purpose of this study was to investigate the efficacy of a composite surgical mesh for delivery of mesenchymal stem cells (MSCs) in tendon repair. Methods The MSC-loaded mesh composed of a piece of conventional surgical mesh and a layer of scaffold, which supported MSC-embedded alginate gel. A 3-mm defect was surgically created at the Achilles tendon-gastrocnemius/soleus junction in 30 rats. The tendon defects were repaired with either 1) MSC-loaded mesh; or 2) surgical mesh only; or 3) routine surgical suture. Repaired tendons were harvested at days 6 and 14 for histology, which was scored on the bases of collagen organization, vascularity and cellularity, and immunohistochemisty of types I and III collagen. Results In comparison with the other two repair types, at day 6, the MSC-loaded mesh significantly improved the quality of the repaired tendons with dense and parallel collagen bundles, reduced vascularity and increased type I collagen. At day 14, the MSC-loaded mesh repaired tendons had better collagen formation and organization. Conclusion The MSC-loaded mesh enhanced early tendon healing, particularly the quality of collagen bundles. Application of the MSC-loaded mesh, as a new device and MSC delivery vehicle, may benefit to early functional recovery of the ruptured tendon. PMID:24884819
Tendon injuries induced by exercise and anabolic steroids in experimental mice
The purpose of this study was to examine the effect of anabolic steroid hormones and exercise training on skeletal tendons. Female mice were exercised for 1 and 10 weeks in an endurance running programme on a treadmill. The altered ultrastructure of tendons caused by simultaneously administered anabolic steroid hormone was investigated by electron microscopy. A stereoscopic analysis of collagen fibrils
H. Michna
Investigation of a tissue engineered tendon model by PS-OCT
A few native tissues, such as tendon, skin and eye, possess highly organized collagenous matrices. In particular, the collagen fibers in tendon are organized into a hierarchical and unidirectional format, which gives rise to the high tissuespecific mechanical properties. This organization has been clearly revealed by a conventional polarized light microscope. The newly developed polarization-sensitive optical coherence tomography (PS-OCT) technique
Ying Yang; Mark Ahearne; Ian Wimpenny; Juan Guijarro-Leach; Jim Torbet
A Comparative Study on Tendon Transfer Surgery in Patients with Radial Nerve Palsy
BACKGROUND Lesions in peripheral nerves are highly prevalent in the upper extremity. The present study compares different tendon transfer surgeries in patients with radial nerve palsy. METHODS Fifty patients with radial nerve palsy were randomly selected among patients who referred to Tehran 15th Khordad Hospital during 2006-2011. They were divided into two groups of 17 and 33 subjects. Single tendon transfer surgery was performed on 33 and ternary tendon transfer surgery on 17 patients and were compared. RESULTS No significant difference was noticed in the range of motion of metacarpophalangeal joint, proximal interphalangeal joint and distal interphalangeal joint joints between the two groups. There was also no significant difference in the results of single tendon and ternary tendon transfer surgeries between the two groups. There was no need to sacrifice three tendons in tendon transfer surgeries on patients with radial nerve palsy. CONCLUSION Single tendon transfer surgery may help establishing a finger extension while indicates to its considerable advantages of surgical simplicity, shorter surgery time, less complications and surgery scars. PMID:25489524
Yavari, Masoud; Abdolrazaghi, Hossein Ali; Riahi, Azadeh
Running exercises improve the strength of a partially ruptured Achilles tendon
Objectives: To examine the effects of running and swimming exercises on the functional performance and mechanical strength of a recovering Achilles tendon.Methods: 30 Sprague-Dawley rats had surgical transection of their right medial Achilles tendon. The rats were divided into running (n = 11), swimming (n = 10), and control (n = 9) groups. The running and swimming groups were given
E K N See; G Y F Ng; C O Y Ng; D T C Fung
We examined the anatomic and biomechanical adequacy of the central quadriceps tendon as an al ternative graft source for anterior cruciate ligament reconstruction. Morphometry was performed on 15 preserved and 6 fresh-frozen specimens. Biomechani cal testing was performed on the six fresh-frozen spec imens. We initially used a triple suture through the tendon construction, and then clamping directly on the
N. Lindsay Harris; David A. B. Smith; Lisa Lamoreaux; Mark Purnell
Semitendinosus and gracilis tendons taken from 25 cadaveric knees were investigated using light and electron microscopy, immunohistochemistry, and morphometry. Thickness of the collagen fibrils, fibril/interstitium ratio, density of blood vessels, density of fibroblasts, and distribution of the collagen fibrils (types I, III, and V collagen and elastic fibers) were analyzed. It was hypothesized that the difference in biomechanical stability between the gracilis and semitendinosus tendons could be reflected by different morphologic features. The results of this study showed that the gracilis tendon, in comparison with the semitendinosus tendon, provides a significantly higher fibril/interstitium ratio and a higher density of collagen III fibers. Conversely, the semitendinosus tendon provides a higher density of blood vessels and collagen I fibers. No differences regarding the density of fibroblasts, thickness of collagen fibrils, and elastic and type V collagen fibers were found. In conclusion, the gracilis tendon graft can provide approximately 15% more collagen than the semitendinosus tendon graft with the same thickness. This fact can play an important role for better biomechanical stability of the gracilis tendon. PMID:18851799
Hadjicostas, Panayiotis T; Soucacos, Panayotis N; Koleganova, Nadezda; Piecha, Grzegorz; Krohmer, Gerhard; Berger, Irina
Rupture sous-cutan�e du tendon long extenseur du pouce: � propos de 5 cas
La rupture spontan�e du muscle long extenseur du pouce (EPL) du tendon au niveau du poignet est rare et principalement rapport�s apr�s fracture du radius distal � tubercule de Lister, dans la synovite, t�nosynovite ou la polyarthrite rhumato�de. Nous rapportons 5 cas de rupture spontan�e du tendon long extenseur du pouce, trait�s par une greffe ou un transfert tendineux. PMID:25317233
Abdelillah, Rachid; Abbassi, Najib; Erraji, Moncef; Abdeljawad, Najib; Yacoubi, Hicham; Daoudi, Abdelkrim
Tendon and Pulleys at the Metacarpophalangeal Joint of a Finger*t
In fresh frozen traumatically amputat- ed forearms with a constant tension of one kilogram on the flexor profundus tendon and the interphahangeal joints fixed in full extension by a Kirschner wire, the excursion of the tendon at the metacarpophalangeal joint and the force at the finger tip were correlated with different angles of flexion of the joint, first with the
The present work displayed the first quantitative data of forces acting on tendons and pulleys during specific sport-climbing grip techniques. A three-dimensional static biomechanical model was used to estimate finger muscle tendon and pulley forces during the �slope� and the �crimp� grip. In the slope grip the finger joints are flexed, and in the crimp grip the distal interphalangeal (DIP)
Laurent Vigouroux; Franck Quaine; Annick Labarre-Vila; Fran�ois Moutet
Force transmission via axial tendons in undulating fish: a dynamic analysis
Sonomicrometrics of in vivo axial strain of muscle has shown that the swimming fish body bends like a homogenous, continuous beam in all species except tuna. This simple beam-like behavior is surprising because the underlying tendon structure, muscle structure and behavior are complex. Given this incongruence, our goal was to understand the mechanical role of various myoseptal tendons. We modeled
John H. Long; Bruce Adcock; Robert G. Root
Rupture of the hamstring tendon is a rare injury. Two cases of complete rupture of the hamstring tendons sustained while playing judo are reported. The diagnosis of a rupture of the hamstring tendons was difficult from physical examination because of severe pain on knee or hip joint movement. Magnetic resonance imaging was non-invasive and showed the lesion clearly. In one
H Kurosawa; K Nakasita; H Nakasita; S Sasaki; S Takeda
The objective of this study was to determine the bio mechanical properties of the healing patellar tendon after removal of its central third. This was accomplished by removing the central third of the patellar tendon from the right limb of 30 mature New Zealand White rabbits. The tendon of the contralateral normal limb served as the unoperated control. The rabbits
Bruce D. Beynnon; Dirk Proffer; David J. Drez; Charles J. Stankewich; Robert J. Johnson
During the last few decades, the incidence of tendon ruptures has increased in civilized countries. Our ma terial comprises 749 patients who had 832 tendon ruptures treated surgically between 1972 and 1985. There were no competitive athletes among the patients studied. There were 292 single ruptures of the Achilles tendon, 274 of the proximal biceps brachii, 113 of the extensor
L. Jozsa; M. Kvist; B. J. Balint; A. Reffy; M. Jarvinen; M. Lehto; M. Barzo
PDGF-BB, IGF-I and mechanical load stimulate DNA synthesis in avian tendon fibroblasts in vitro
Resident cells in the surface epitenon and internal compartment of flexor tendons are subjected to cyclic mechanical load as muscle contracts to move limbs or digits. Tendons are largely tensile load bearing tissues and are highly matrix intensive with nondividing cells providing maintenance functions. However, when an injury occurs, tendon cells are stimulated to divide by activated endogenous growth factors
Albert J. Banes; Mari Tsuzaki; Peiqi Hu; Brian Brigman; Thomas Brown; Louis Almekinders; W. Thomas Lawrence; Thomas Fischer
Spatial variations in Achilles tendon shear wave speed Ryan J. DeWall a,b,n
. Introduction Achilles tendon injury, e.g. tendinopathy, can lead to chronic pain and impairment. The choiceSpatial variations in Achilles tendon shear wave speed Ryan J. DeWall a,b,n , Laura C. Slane c in Achilles tendon shear wave speed that occurs with loading, an effect attributable to the strain
Wisconsin at Madison, University of
The current report presents the case of a 41-year-old male exhibiting a giant cell tumor of the tendon sheath (GCT-TS) arising from the patellar tendon sheath. Plain radiography and magnetic resonance imaging revealed a well-localized mass that wrapped around the patellar tendon, and extended from the subcutis into the infrapatellar fat pad and tibia. Following histopathological determination of the diagnosis, a piecemeal resection was performed. Nodular-type GCT-TS occurs less frequently in large joints compared with the small joints of the fingers and toes. The current report presents the unique features of a case of GCT-TS extending around the patellar tendon, and invading into the knee joint and proximal tibia bone. PMID:25360180
Parameter maps of 1H residual dipolar couplings in tendon under mechanical load
NASA Astrophysics Data System (ADS)
Proton multipolar spin states associated with dipolar encoded longitudinal magnetization (DELM) and double-quantum (DQ) coherences of bound water are investigated for bovine and sheep Achilles tendon under mechanical load. DELM decay curves and DQ buildup and decay curves reveal changes of the 1H residual dipolar couplings for tendon at rest and under local compression forces. The multipolar spin states are used to design dipolar contrast filters for NMR 1H images of heterogeneous tendon. Heterogeneities in tendon samples were artificially generated by local compression parallel and perpendicular to the tendon plug axis. Quotient images obtained from DQ-filtered images by matched and mismatched excitation/reconversion periods are encoded only by the residual dipolar couplings. Semi-quantitative parameter maps of the residual dipolar couplings of bound water were obtained from these quotient images using a reference elastomer sample. This method can be used to quantify NMR imaging of injured ordered tissues.
Fechete, R.; Demco, D. E.; Bl�mich, B.
Mechanical factors in embryonic tendon development: Potential cues for stem cell tenogenesis
Tendons are connective tissues required for motion and are frequently injured. Poor healing and inadequate return to normal tissue structure and mechanical function make tendon a prime candidate for tissue engineering, however functional tendons have yet to be engineered. The physical environment, from substrate stiffness to dynamic mechanical loading, may regulate tenogenic stem cell differentiation. Tissue stiffness and loading parameters derived from embryonic development may enhance tenogenic stem cell differentiation and tendon tissue formation. We highlight current understanding of the mechanical environment experienced by embryonic tendons and how progenitor cells may sense and respond to physical inputs. We further discuss how mechanical factors have only recently been used to induce tenogenic fate in stem cells. PMID:23916867
Schiele, Nathan R.; Marturano, Joseph E.; Kuo, Catherine K.
Re-revision of a patellar tendon rupture in a young professional martial arts athlete.
A 27-year-old professional martial arts athlete experienced recurrent right knee patellar tendon rupture on three occasions. He underwent two operations for complete patellar tendon rupture: an end-to-end tenorrhaphy the first time, and revision with a bone-patellar-tendon (BPT) allograft. After the third episode, he was referred to our department, where we performed a surgical reconstruction with the use of hamstring pro-patellar tendon, in a figure-of-eight configuration, followed by a careful rehabilitation protocol. Clinical and radiological follow-ups were realized at 1, 3, and 6 months and 1 and 2 years postop, with an accurate physical examination, the use of recognized international outcome scores, and radiograph and MRI studies. As far as we know, this is the first paper to report a re-revision of a patellar tendon rupture. PMID:22008978
Vadal�, A; Iorio, R; Bonifazi, A M; Bolle, G; Ferretti, A
Injury induces a change in the functional characteristics of cells recovered from equine tendon.
Injury initiates a repair process characterized by influx of fibroblasts and the rapid formation of fibrous scar tissue and subsequent tissue contraction. The response to injury and behavior of the different tendon fibroblast populations, however, has been poorly characterized. We hypothesized that the fibroblasts recovered from tendon with acute injury would exhibit different cell properties relating to adhesion, migration and tensegrity. To test this hypothesis we evaluated the ability of fibroblasts recovered from normal and injured equine superficial digital flexor tendons (SDFTs). The injured tendon-derived cells showed greater contraction of the collagen gel but poorer adhesion to pepsin-digested collagen, and migration over extracellular matrix proteins compared to normal SDFT-derived fibroblasts. Thus, the cells present within the tendon after injury display different behavior related to wound healing. PMID:24833988
Kihara, Rina; Kasashima, Yoshinori; Arai, Katsuhiko; Miyamoto, Yasunori
Sonographic findings during and after Platelet Rich Plasma injections in tendons
Summary Platelet rich plasma has been used in the treatment of tendinopathies, but the sonographic modifications of tendons have received less attention. In this paper we report the results of an ultrasound evaluation, performed during and after plasma injection, in patients with tendinopathy. The sonographic abnormalities and neovascularization were registered in twenty tendons. Three plasma injections (once a week) were performed, and a rehabilitation program was recommended. Pain and patients� satisfaction were evaluated. During the injections plasma spread along the collagen fibers, and an intratendineous cleft produced by the injected volume was observed. At 12 months two tendons regained a normal echotexture, while neovessels were absent in seven. The remaining tendons showed less abnormalities and neovascularization in comparison with baseline. The clinical improvement was earlier and more consistent. The discrepancy between the ultrasound and clinical results may be explained by the peculiar modalities of tendon healing induced by plasma administration. PMID:24932444
Abate, Michele; Verna, Sandra; Di Gregorio, Patrizia; Salini, Vincenzo; Schiavone, Cosima
Variability in Hoffmann and tendon reflexes in healthy male subjects
NASA Technical Reports Server (NTRS)
There is a time dependent decrease in amplitude of H- and T-reflexes during Zero-G exposure and subsequently an increase in the amplitude of the H-reflex 2-4 hours after return to a 1-G environment. These alterations have been attributed to the adaptation of the human neurosensory system to gravity. The Hoffman reflex (H-reflex) is an acknowledged method to determine the integrity of the monosynaptic reflex arc. However deep tendon reflexes (DTR's or T-reflexes), elicited by striking the tendon also utilize the entire reflex arc. The objective of this study was to compare the variability in latency and amplitude of the two reflexes in healthy subjects. Methods: Nine healthy male subjects, 27-43 years in age, 161-175 cm in height plus 60-86 Kg in weight, underwent weekly testing for four weeks with a Dan-Tec EMG counterpoint EMG system. Subjects were studied prone and surface EMG electrodes were placed on the right and left soleus muscles. The H-reflex was obtained by stimulating the tibial nerve in the politeal fossa with a 0.2 msec square wave pulse delivered at 2 Hz until the maximum H-reflex was obtained. The T-reflex was invoked by tapping the achilles tendon with a self triggering reflex hammer connected to the EMG system. The latencies and amplitudes for the H- and T-reflexes were measured. Results: These data indicate that the amplitudes of these reflexes varied considerably. However, latencies to invoked responses were consistent. The latency of the T-reflex was approximately 3-5 msec longer than the H-reflex. Conclusion: The T-reflex is easily obtained, requires less time, and is more comfortable to perform. Qualitative data can be obtained by deploying self triggering, force plated reflex hammers both in the 1-G and Zero-G environment.
Good, E.; Do, S.; Jaweed, M.
Background: Debate exists regarding the optimal graft for anterior cruciate ligament reconstruction. Few studies have compared the differences in outcome after reconstruction using similar fixation methods.Hypothesis: Similar outcomes will be seen after anterior cruciate ligament reconstruction with bone-patellar tendon-bone or quadruple-strand semitendinosus\\/gracilis tendons fixed with bioabsorbable interference screws.Study Design: Randomized controlled trial; Level of evidence, 1.Methods: Ninety-nine patients were prospectively
Gregory B. Maletis; Sheri L. Cameron; Joann J. Tengan; Raoul J. Burchette
Indicators of replicative damage in equine tendon fibroblast monolayers
Background Superficial digital flexor tendon (SDFT) injuries of horses usually follow cumulative matrix microdamage; it is not known why the reparative abilities of tendon fibroblasts are overwhelmed or subverted. Relevant in vitro studies of this process require fibroblasts not already responding to stresses caused by the cell culture protocols. We investigated indicators of replicative damage in SDFT fibroblast monolayers, effects of this on their reparative ability, and measures that can be taken to reduce it. Results We found significant evidence of replicative stress, initially observing consistently large numbers of binucleate (BN) cells. A more variable but prominent feature was the presence of numerous gammaH2AX (?H2AX) puncta in nuclei, this being a histone protein that is phosphorylated in response to DNA double-stranded breaks (DSBs). Enrichment for injury detection and cell cycle arrest factors (p53 (ser15) and p21) occurred most frequently in BN cells; however, their numbers did not correlate with DNA damage levels and it is likely that the two processes have different causative mechanisms. Such remarkable levels of injury and binucleation are usually associated with irradiation, or treatment with cytoskeletal-disrupting agents. Both DSBs and BN cells were greatest in subconfluent (replicating) monolayers. The DNA-damaged cells co-expressed the replication markers TPX2/repp86 and centromere protein F. Once damaged in the early stages of culture establishment, fibroblasts continued to express DNA breaks with each replicative cycle. However, significant levels of cell death were not measured, suggesting that DNA repair was occurring. Comet assays showed that DNA repair was delayed in proportion to levels of genotoxic stress. Conclusions Researchers using tendon fibroblast monolayers should assess their �health� using ?H2AX labelling. Continued use of early passage cultures expressing initially high levels of ?H2AX puncta should be avoided for mechanistic studies and ex-vivo therapeutic applications, as this will not be resolved with further replicative cycling. Low density cell culture should be avoided as it enriches for both DNA damage and mitotic defects (polyploidy). As monolayers differing only slightly in baseline DNA damage levels showed markedly variable responses to a further injury, studies of effects of various stressors on tendon cells must be very carefully controlled. PMID:24025445
Effects of fluoride on in vitro calcification of tendon matrix
Summary Ca2+ and Pi uptake induced in vitro by a collagenous matrix derived from bovine tendon is inhibited by 1�10?6 to 2�10?5M NaF and stimulated by 2�10?5 to 2�10?3M NaF. Fluoride uptake occurs only over the latter concentrtion range. The uptake of Ca2+, Pi, and F?1 progresses toward a limiting extent at which the molar Ca\\/P and Ca\\/F values are
C. L. Wadkins; R. A. Luben
Uptake swelling and thermal expansion of CFRP tendons
, using Lame��s equations for thick-walled cylinders. The concrete has a Young�s modulus Ec and Poisson�s ratio #1;c, whereas the FRP tendon has a transverse Young�s modulus E22 and transverse Poisson�s ratio #1;23. It is assumed that the axial stress, #2... to reflect FRP swelling. At the limit of the partly cracked stage, a longitudinal crack extends throughout the concrete cover. However, if the concrete deforms plastically, a higher ultimate load may be achieved. Hence, Tepfers34 also introduces an uncracked...
Scott, P.; Lees, Janet M.
Spontaneous rupture of the gluteus medius and minimus tendons.
Tears and tendinopathy of the gluteus medius and minimus are potentially underrecognized clinical sources of hip pain. Magnetic resonance imaging is useful in diagnosing gluteal tears. This entity is frequently a result of predisposing conditions but may arise spontaneously. This clinical problem should be considered in the differential diagnosis of patients presenting with acute hip pain. In this article, we report a case of spontaneous rupture of the gluteus medius and minimus tendons in a previously healthy patient with no prior hip symptoms. PMID:12405564
Lonner, Jess H; Van Kleunen, Jonathan P
Comparison of CO2 laser welding with suture technique for repair of tendons
NASA Astrophysics Data System (ADS)
The purpose of this study was to evaluate the efficacy, histology, and strength of laser welding in repair of sharply transected rat Achilles tendons. In 26 adult, male Sprague-Dawley rats, the severed tendons were repaired with a 7-0 nylon, modified Kessler core suture followed by either a running 9-0 nylon epitendinous suture or a circumferential CO2 laser epidendinous weld using 25% human albumin as a solder. All repairs were timed and post- operative tensile strength was analyzed with material testing equipment. In addition, histologic testing was performed on both types of repairs. The mean time to complete the epitendinous repair in the laser group was 3.5 minutes and in the suture group, 8 minutes. The mean ultimate tensile strength in 6 normal tendons was 40.9 Newtons (N) with group standard deviation of 5.2 N. When compared with normal controls, post-operatively both types of tendon repairs resulted in tensile failure at lower forces. The ultimate tensile strength for the epitendinous suture repair and the laser welds were 13% and 6% of normal controls, respectively. Twenty tendons with epidendinous suture repair had mean ultimate tensile strength of 5.4 (+/- 1.2) N, while the 17 tendons with laser wends failed at 2.6 (+/- 0.9) N. Histologic evaluation of tendons repaired with CO2 laser revealed areas of coagulation and edema on the surface of tendon edges. Post-operatively, greater tissue changes were noted in laser treated tendons than those repaired with sutures. Laser welding of epitenon is possible and can be completed faster than the suture repair. The repaired tendon surface appears smoother and less bulky after laser treatment. However, significantly decreased immediate post-operative strength was demonstrated by the use of Kruskal-Wallis one way analysis of variance and Turkey's pairwise comparison.
Popovic, Neven A.; Johnstone, Frederic L.; Kilkelly, Francis X.; McKinney, LuAnn; Van De Merwe, Willem P.; Smith, Allan C.
Children develop lower levels of muscle force, and at slower rates, than adults. Although strength training in children is expected to reduce this differential, a synchronous adaptation in the tendon must be achieved to ensure forces continue to be transmitted to the skeleton with efficiency while minimizing the risk of strain-related tendon injury. We hypothesized that resistance training (RT) would alter tendon mechanical properties in children concomitantly with changes in force production characteristics. Twenty prepubertal children (age 8.9 � 0.3 yr) were equally divided into control (nontraining) and experimental (training) groups. The training group completed a 10-wk RT intervention consisting of 2�3 sets of 8�15 plantar flexion contractions performed twice weekly on a recumbent calf-raise machine. Achilles tendon properties (cross-sectional area, elongation, stress, strain, stiffness, and Young's modulus), electromechanical delay (EMD; time between the onset of muscle activity and force), rate of force development (RFD; slope of the force-time curve), and rate of electromyographic (EMG) increase (REI; slope of the EMG time curve) were measured before and after RT. Tendon stiffness and Young's modulus increased significantly after RT in the experimental group only (?29% and ?25%, respectively); all other tendon properties were not significantly altered, although there were mean decreases in both peak tendon strain and strain at a given force level (14% and 24%, respectively; not significant) which may have implications for tendon injury risk and muscle fiber mechanics. A decrease of ?13% in EMD was found after RT for the experimental group, which paralleled the increase in tendon stiffness (r = ?0.59); however, RFD and REI were unchanged. The present data show that the Achilles tendon adapts to RT in prepubertal children and is paralleled by a change in EMD, although the magnitude of this change did not appear to be sufficient to influence RFD. These findings are of importance within the context of the efficiency and execution of movement. PMID:24903920
Waugh, C. M.; Korff, T.; Fath, F.
Adhesions in a Murine Flexor Tendon Graft Model: Autograft versus Allograft Reconstruction
Reconstruction of flexor tendons often results in adhesions that compromise joint flexion. Little is known about the factors involved in the formation of flexor tendon graft adhesions. In this study, we developed and characterized a novel mouse model of flexor digitorum longus (FDL) tendon reconstruction with live autografts or reconstituted freeze-dried allografts. Grafted tendons were evaluated at multiple time points up to 84 days post-reconstruction. To assess the flexion range of the metatarsophalangeal joint, we developed a quantitative outcome measure proportional to the resistance to tendon gliding due to adhesions, which we termed the Gliding Coefficient. At 14 days post grafting, the Gliding Coefficient was 29- and 26-fold greater than normal FDL tendon for both autografts and allografts, respectively (p<0.001), and subsequently doubled for 28-day autografts. Interestingly, there were no significant differences in maximum tensile force or stiffness between live autograft and freeze-dried allograft repairs over time. Histologically, autograft healing was characterized by extensive remodeling and exuberant scarring around both the ends and the body of the graft, whereas allograft scarring was abundant only near the graft-host junctions. Gene expression of GDF-5 and VEGF were significantly increased in 28 day autografts compared to allografts and to normal tendons. These results suggest that the biomechanical advantages for tendon reconstruction using live autografts over devitalized allografts are minimal. This mouse model can be useful in elucidating the molecular mechanisms in tendon repair and can aid in preliminary screening of molecular treatments of flexor tendon adhesions. PMID:18186128
Hasslund, S; Jacobson, JA; Dadali, T; Basile, P; Ulrich-Vinther, M; Soballe, K; Schwarz, EM; O�Keefe, RJ; Mitten, DJ; Awad, HA
Col V siRNA engineered tenocytes for tendon tissue engineering.
The presence of uniformly small collagen fibrils in tendon repair is believed to play a major role in suboptimal tendon healing. Collagen V is significantly elevated in healing tendons and plays an important role in fibrillogenesis. The objective of this study was to investigate the effect of a particular chain of collagen V on the fibrillogenesis of Sprague-Dawley rat tenocytes, as well as the efficacy of Col V siRNA engineered tenocytes for tendon tissue engineering. RNA interference gene therapy and a scaffold free tissue engineered tendon model were employed. The results showed that scaffold free tissue engineered tendon had tissue-specific tendon structure. Down regulation of collagen V ?1 or ?2 chains by siRNAs (Col5?1 siRNA, Col5?2 siRNA) had different effects on collagen I and decorin gene expressions. Col5?1 siRNA treated tenocytes had smaller collagen fibrils with abnormal morphology; while those Col5?2 siRNA treated tenocytes had the same morphology as normal tenocytes. Furthermore, it was found that tendons formed by coculture of Col5?1 siRNA treated tenocytes with normal tenocytes at a proper ratio had larger collagen fibrils and relative normal contour. Conclusively, it was demonstrated that Col V siRNA engineered tenocytes improved tendon tissue regeneration. And an optimal level of collagen V is vital in regulating collagen fibrillogenesis. This may provide a basis for future development of novel cellular- and molecular biology-based therapeutics for tendon diseases. PMID:21713001
Lu, Ping; Zhang, Guo Rong; Song, Xing Hui; Zou, Xiao Hui; Wang, Lin Lin; Ouyang, Hong Wei
Col V siRNA Engineered Tenocytes for Tendon Tissue Engineering
The presence of uniformly small collagen fibrils in tendon repair is believed to play a major role in suboptimal tendon healing. Collagen V is significantly elevated in healing tendons and plays an important role in fibrillogenesis. The objective of this study was to investigate the effect of a particular chain of collagen V on the fibrillogenesis of Sprague-Dawley rat tenocytes, as well as the efficacy of Col V siRNA engineered tenocytes for tendon tissue engineering. RNA interference gene therapy and a scaffold free tissue engineered tendon model were employed. The results showed that scaffold free tissue engineered tendon had tissue-specific tendon structure. Down regulation of collagen V ?1 or ?2 chains by siRNAs (Col5?1 siRNA, Col5?2 siRNA) had different effects on collagen I and decorin gene expressions. Col5?1 siRNA treated tenocytes had smaller collagen fibrils with abnormal morphology; while those Col5?2 siRNA treated tenocytes had the same morphology as normal tenocytes. Furthermore, it was found that tendons formed by coculture of Col5?1 siRNA treated tenocytes with normal tenocytes at a proper ratio had larger collagen fibrils and relative normal contour. Conclusively, it was demonstrated that Col V siRNA engineered tenocytes improved tendon tissue regeneration. And an optimal level of collagen V is vital in regulating collagen fibrillogenesis. This may provide a basis for future development of novel cellular- and molecular biology-based therapeutics for tendon diseases. PMID:21713001
Song, Xing Hui; Zou, Xiao Hui; Wang, Lin Lin; Ouyang, Hong Wei
Force transmission via axial tendons in undulating fish: a dynamic analysis.
Sonomicrometrics of in vivo axial strain of muscle has shown that the swimming fish body bends like a homogenous, continuous beam in all species except tuna. This simple beam-like behavior is surprising because the underlying tendon structure, muscle structure and behavior are complex. Given this incongruence, our goal was to understand the mechanical role of various myoseptal tendons. We modeled a pumpkinseed sunfish, Lepomis gibbosus, using experimentally-derived physical and mechanical attributes, swimming from rest with steady muscle activity. Axially oriented muscle-tendons, transverse and axial myoseptal tendons, as suggested by current morphological knowledge, interacted to replicate the force and moment distribution. Dynamic stiffness and damping associated with muscle activation, realistic muscle force generation, and force distribution following tendon geometry were incorporated. The vertebral column consisted of 11 rigid vertebrae connected by joints that restricted bending to the lateral plane and endowed the body with its passive viscoelasticity. In reaction to the acceleration of the body in an inviscid fluid and its internal transmission of moment via the vertebral column, the model predicted the kinematic response. Varying only tendon geometry and stiffness, four different simulations were run. Simulations with only intrasegmental tendons produced unstable axial and lateral tail forces and body motions. Only the simulation that included both intra- and intersegmental tendons, muscle-enhanced segment stiffness, and a stiffened caudal joint produced stable and large lateral and axial forces at the tail. Thus this model predicts that axial tendons function within a myomere to (1) convert axial force to moment (moment transduction), (2) transmit axial forces between adjacent myosepta (segment coupling), and, intersegmentally, to (3) distribute axial forces (force entrainment), and (4) stiffen joints in bending (flexural stiffening). The fact that all four functions are needed to produce the most realistic swimming motions suggests that axial tendons are essential to the simple beam-like behavior of fish. PMID:12485683
Long, John H; Adcock, Bruce; Root, Robert G
The role of intrinsic and extrinsic healing in injured tendons is still debated. In this study, we characterized cell plasticity, proliferative capacity, and migration characteristics as proxy measures of healing potential in cells derived from the peritenon (extrinsic healing) and compared these to cells from the tendon core (intrinsic healing). Both cell populations were extracted from horse superficial digital flexor tendon and characterized for tenogenic and matrix remodeling markers as well as for rates of migration and replication. Furthermore, colony-forming unit assays, multipotency assays, and real-time quantitative polymerase chain reaction analyses of markers of osteogenic and adipogenic differentiation after culture in induction media were performed. Finally, cellular capacity for differentiation towards a myofibroblastic phenotype was assessed. Our results demonstrate that both tendon- and peritenon-derived cell populations are capable of adipogenic and osteogenic differentiation, with higher expression of progenitor cell markers in peritenon cells. Cells from the peritenon also migrated faster, replicate more quickly, and show higher differentiation potential toward a myofibroblastic phenotype when compared to cells from the tendon core. Based on these data, we suggest that cells from the peritenon have substantial potential to influence tendon-healing outcome, warranting further scrutiny of their role. PMID:24651449
Cadby, Jennifer A.; Buehler, Evelyne; Godbout, Charles; van Weeren, P. Ren�; Snedeker, Jess G.
materials [4]-[6].Collagen content varies according to the type of animal and tendon. Achilles tendon from in Mammalian Tendon Threads Using Various Reference Media CHARLESA. EDWARDS AND WILLIAM D. O'BRIEN, JR., SENIOR- amined on its acoustic properties is demonstrated. Mammalian tendon threads (on the order of 150 pm
Illinois at Urbana-Champaign, University of
Mechanical properties of the human achilles tendon Tishya A.L. Wren a,b,*, Scott A. Yerby a,b
Mechanical properties of the human achilles tendon Tishya A.L. Wren a,b,*, Scott A. Yerby a October 2000 Abstract Objective. To determine whether the human Achilles tendon has higher material testing of excised tendons. Background. While the human Achilles tendon appears to experience higher
Stanford University
Repair of the torn distal biceps tendon by endobutton fixation
Background: A number of techniques have been described to reattach the torn distal biceps tendon to the bicipital tuberosity. We report a retrospective analysis of single incision technique using an endobutton fixation in sports persons. Materials and Methods: The present series include nine torn distal biceps tendons in eight patients, fixed anatomically to the radial tuberosity with an endobutton by using a single incision surgical technique; seven patients had suffered the injuries during contact sports. The passage of the endobutton was facilitated by using a blunt tipped pin in order to avoid injury to the posterior interosseous nerve. The patients were evaluated by Disabilities of the Arm, Shoulder and Hand (DASH) score and Mayo elbow score. Results: The average age of the patients was 27.35 years (range 21�42 years). Average follow-up was 41.5 months (range 24�102 months). The final average flexion extension arc was 0��143�, while the average pronation and supination angles were 77� (range 70��82�) and 81� (range 78��85�), respectively at the last followup. All the patients had a Disabilities of the Arm, Shoulder and Hand (DASH) score of 0 and a Mayo elbow score of 100 each. All the seven active sports persons were able to get back to their respective game. There was no nerve injury or any other complication. Conclusions: The surgical procedure used by us is a simple, safe and reproducible technique giving minimal morbidity and better cosmetic results. PMID:22345810
Gupta, Ravi K; Bither, Nitin; Singh, Harpreet; Kapoor, Saurabh; Chhabra, Ashish; Garg, Sudhir
Anthropometric risk factors for patellar tendon injury among volleyball players
Objective Abnormal imaging in the patellar tendon reveals pathology that is often associated with knee pain. Anthropometric measures of body size and mass, such as height, weight and waist?to?hip ratio (WHR), have been individually associated with abnormal imaging. The aim of this study was to investigate the anthropometric factors that have the strongest relationship with abnormal imaging in volleyball players. Methods Height, weight, body mass index (BMI), waist girth, hip girth and WHR were measured in a cohort of 113 competitive volleyball players (73 men, 40 women). The univariate (ANOVA) and multivariable (discriminant function analysis) association between abnormal imaging and these anthropometric factors were investigated. Results No significant association was found in the female volleyball players. A significant univariate association was observed between abnormal imaging and heavier weight, greater BMI, larger waist and hip girth and larger WHR in the male volleyball players. Waist girth was the only factor that retained this association in a multivariable model (p<0.05). Conclusions Men with a waist girth greater than 83?cm seem to be at greater risk of developing patellar tendon pathology. There may be both mechanical and biochemical reasons for this increased risk. PMID:16920767
Malliaras, P; Cook, J L; Kent, P M
An Isolated Medial Patellofemoral Ligament Reconstruction with Patellar Tendon Autograft
The aim of the study was to evaluate the results of the medial patellofemoral ligament reconstruction with a medial strip of patellar tendon autograft after a minimum 2-year followup. Ten patients (10 knees) were operated on by one surgeon, according to the modified technique, described by Camanho, without any bone plug at free graft end. The mean age of the patients was 27.2 years (ranging from 18 to 42 years). The mean follow-up period was 3 years and 7 months. All patients were reviewed prospectively. At the last follow-up visit, all the patients demonstrated a significant improvement in terms of patellofemoral joint stability, all aspects of the KOOS questionnaire, and Kujala et al.'s score (59.7 points preoperatively and 84.4 points at the last followup). No patient revealed recurrent dislocation. The SF-36 score revealed a significant improvement in bodily pain, general health, physical role functioning, social role functioning, and physical functioning domains. The described MPFL reconstruction with the use of the medial 1/3rd of patella tendon is an effective procedure that gives satisfactorily patellofemoral joint functions, improves the quality of life, and provides much pain relief. It is relatively simple, surgically not extensive, and economically cost-effective procedure. PMID:24224173
Wito?ski, Dariusz; K?ska, Rafa?; Synder, Marek; Sibi?ski, Marcin
Mechanical properties of decellularized tendon cultured by cyclic straining bioreactor.
Decellularized tissues have been successfully used in tissue engineering and regenerative medicine for the purpose of removing antigens present in the cellular components. However, this decellularization technique uses ionic solutions or chemical treatments such as enzyme treatments that might damage the biophysical properties or reduce the physical strength of tissue. This study aimed to improve the strength of decellularized tissues. We designed a tissue bioreactor that can repeatedly deliver physical stimulation, such as tensile and torsional deformation, to the upper and lower parts of a tissue. To decellularized porcine Tibialis tendons, we used an enzymatic solution to remove the primary cells, and then applied ultrasonic cleansing using a combination of ionic solution and distilled water to destroy residual cells by differing from the osmotic pressure between the inside and outside of the cell membrane. The total DNA content of decellularized tissue was decreased by 77% compared with that of the original tissue and the ultimate tensile strength of the decellularized tissue was 20% lower than that of the normal tissue. Decellularized tissues were then cultivated in the tissue bioreactor with repeated physical stimulation of 110% tension, 90� torsion, and frequency of once per a second, and the ultimate tensile strength was found to be greater than that of the normal ligament at 7 day culture. This study showed that decellularization using enzyme and mechanical treatment is safe and use of a tissue bioreactor can increase the physical strength of tendons, making this a potential mechanism to reconstruct human ligaments. PMID:23554286
Lee, Kwang-Il; Lee, Jung-Soo; Kim, Jin-Gu; Kang, Kyoung-Tak; Jang, Ju-Woong; Shim, Young-Bock; Moon, Seong-Hwan
Fiber optic micro sensor for the measurement of tendon forces
A fiber optic sensor developed for the measurement of tendon forces was designed, numerically modeled, fabricated, and experimentally evaluated. The sensor incorporated fiber Bragg gratings and micro-fabricated stainless steel housings. A fiber Bragg grating is an optical device that is spectrally sensitive to axial strain. Stainless steel housings were designed to convert radial forces applied to the housing into axial forces that could be sensed by the fiber Bragg grating. The metal housings were fabricated by several methods including laser micromachining, swaging, and hydroforming. Designs are presented that allow for simultaneous temperature and force measurements as well as for simultaneous resolution of multi-axis forces. The sensor was experimentally evaluated by hydrostatic loading and in vitro testing. A commercial hydraulic burst tester was used to provide uniform pressures on the sensor in order to establish the linearity, repeatability, and accuracy characteristics of the sensor. The in vitro experiments were performed in excised tendon and in a dynamic gait simulator to simulate biological conditions. In both experimental conditions, the sensor was found to be a sensitive and reliable method for acquiring minimally invasive measurements of soft tissue forces. Our results suggest that this sensor will prove useful in a variety of biomechanical measurements. PMID:23033868
Energy storing tendons, such as the human Achilles and equine superficial digital flexor tendon (SDFT), are highly prone to injury, the incidence of which increases with aging. The cellular and molecular mechanisms that result in increased injury in aged tendons are not well established but are thought to result in altered matrix turnover. However, little attempt has been made to fully characterize the tendon proteome nor determine how the abundance of specific tendon proteins changes with aging and/or injury. The aim of this study was, therefore, to assess the protein profile of normal SDFTs from young and old horses using label-free relative quantification to identify differentially abundant proteins and peptide fragments between age groups. The protein profile of injured SDFTs from young and old horses was also assessed. The results demonstrate distinct proteomic profiles in young and old tendon, with alterations in the levels of proteins involved in matrix organization and regulation of cell tension. Furthermore, we identified several new peptide fragments (neopeptides) present in aged tendons, suggesting that there are age-specific cleavage patterns within the SDFT. Proteomic profile also differed between young and old injured tendon, with a greater number of neopeptides identified in young injured tendon. This study has increased the knowledge of molecular events associated with tendon aging and injury, suggesting that maintenance and repair of tendon tissue may be reduced in aged individuals and may help to explain why the risk of injury increases with aging. PMID:25077967
Peffers, Mandy J.; Thorpe, Chavaunne T.; Collins, John A.; Eong, Robin; Wei, Timothy K. J.; Screen, Hazel R. C.; Clegg, Peter D.
Using an alternative soaking process improved the tendon-bone attachment for a calcium phosphate (CaP)-hybridized tendon graft. We characterized the deposited CaP on and in tendons and analyzed the histology and mechanical properties of the tendon-bone interface in anterior cruciate ligament (ACL) reconstruction in goats. The tendon grafts to be implanted were soaked ten times alternately in a Ca-containing solution and a PO(4)-containing solution for 30 s each. Needlelike CaP nanocrystals including low-crystalline apatite were deposited on and between collagen fibrils from the surface to a depth of 200 microm inside the tendon. The structure resembles the extracellular matrix of bone. In animal experiments, the CaP-hybridized tendon directly bonded with newly formed bone at 6 weeks (n = 3), while fibrous bonding was observed in the control (n = 3). The ultimate failure load was not statistically different between the CaP (n = 7) and control (n = 7). However, in the failure mode, all the tendon-bone interfaces were intact in the CaP group, while three of seven specimens were pulled out from bone tunnels in the control. The result suggested that the strength of the tendon-bone interface in the CaP group is superior to that in the control group. Clinically, firm tendon-bone anchoring may lead to good results without the knee instability associated with the loosening of the bone-tendon junction in ACL reconstruction. PMID:19667461
Mutsuzaki, Hirotaka; Sakane, Masataka; Hattori, Shinya; Kobayashi, Hisatoshi; Ochiai, Naoyuki
Resurfacing with Chemically Modified Hyaluronic Acid and Lubricin for Flexor Tendon Reconstruction
We assessed surface coating with carbodiimide derivatized hyaluronic acid combined with lubricin (cd-HA-Lubricin) as a way to improve extrasynovial tendon surface quality and, consequently, the functional results in flexor tendon reconstruction, using a canine in vivo model. The second and fifth flexor digitorum profundus tendons from 14 dogs were reconstructed with autologs peroneus longus (PL) tendons 6 weeks after a failed primary repair. One digit was treated with cd-HA-Lubricin, and the other was treated with saline as the control. Six weeks following grafting, the digits and graft tendons were functionally and histologically evaluated. Adhesion score, normalized work of flexion, graft friction in zone II, and adhesion breaking strength at the proximal repair site in zone III were all lower in the cd-HA-Lubricin treated group compared to the control group. The strength at the distal tendon/bone interface was decreased in the cd-HA-Lubricin treated grafts compared to the control grafts. Histology showed inferior healing in the cd-HA-Lubricin group at both proximal and distal repair sites. However, cd-HA-Lubricin treatment did not result in any gap or rupture at either the proximal or distal repair sites. These results demonstrate that cd-HA-Lubricin can eliminate graft adhesions and improve digit function, but that treatment may have an adverse effect on tendon healing. PMID:23335124
Zhao, Chunfeng; Hashimoto, Takahiro; Kirk, Ramona L.; Thoreson, Andrew R.; Jay, Gregory D.; Moran, Steven L.; An, Kai-Nan; Amadio, Peter C.
This study investigated the effects of hybridized micro and nano structured collagen implants on tendon healing in an experimental tendon injury in rabbits. Fifty mature male New Zealand white rabbits were randomly divided into two groups of treated and control. Two cm of the left Achilles tendon were discarded. In the treated group, a 3-dimensional (3D) collagen implant was engineered and implanted in the defect area. No implant was used in the control group. At day 120 after injury, the Achilles tendon of the animals were ultrasonographically (days 0-120 after injury) and radiographically (day 120 after injury) examined, and the animals were euthanized. The tendons were dissected and used for gross pathological, histopathological, ultra-structural and biomechanical investigations. Application of the collagen implant significantly increased the diameter of the newly regenerated tissue in the defect area compared to the control tendons. Treatment also significantly increased the echogenicity and homogeneity of the injured area, the diameter of the collagen fibrils and fibers, maturity of the tenoblasts, number of tenocytes, collagen density, alignment, ultimate and yield load, stiffness, stress and modulus of elasticity. The collagen implants were almost totally absorbed 120 days after surgery. No inflammatory reaction or tissue degeneration or necrosis was evident in the treated tendons compared to the control ones. 3D collagen implants produced a newly regenerated tendinous tissue at the defect area that was morphologically and biomechanically superior to the control group. This collagen implant was biocompatible and biodegradable with high bio-safety in rabbits. PMID:25316127
Moshiri, A; Oryan, A; Meimandiparizi, A; Maffulli, N