title: Epidemiology of chronic non-malignant pain in Denmark Clinical precision of myofascial trigger point location in the trapezius muscle Intertester reliability of judgments of the presence of trigger points in patients with low back pain. Interexaminer reliability of the palpation of trigger points in the trunk and lower limb muscles. The occurrence and inter-rater reliability of myofascial trigger points in the quadratus lumborum and gluteus medius: a prospective study in non-specific low back pain patients and controls in general practice. Test-retest reliability of myofascial trigger point detection in patients with rotator cuff tendonitis Interrater reliability in myofascial trigger point examination Endplate Potentials Are Common to Midfiber Myofacial Trigger Points Reliability of clinical temporomandibular disorder diagnoses The annual incidence and course of neck pain in the general population: a population-based cohort study Research Diagnostic Criteria for Temporomandibular Disorders: A Calibration and Reliability Study The prevalence of pain in a general population. The results of a postal survey in a county of Sweden Chronic low back pain in older adults: prevalence, reliability, and validity of physical examination findings. A cross-national study of the course of persistent pain in primary care Chronic pain, work performance and litigation Chronic pain in Australia: a prevalence study
abstract: & NA ; A series of health surveys are conducted every sixth to seventh year in Denmark . In the most recent survey of 2000 , a national r and om sample ( > 16 years ) was drawn from the Danish Central Personal Register . Out of the original sample 12,333 ( 74 % ) were interviewed and of these 10,066 returned a completed question naire ( SF‐36 ) . The present study includes only those who both took part in the interview and the postal question naire . Cancer patients were excluded . Persons suffering from chronic pain ( PG ) were identified through the question ‘ Do you have chronic/long lasting pain lasting 6 months or more ’ ? An overall chronic pain prevalence of 19 % was found −16 % for men and 21 % for women . Prevalence of chronic pain increased with increasing age . Persons ≥67 years had 3.9 higher odds of suffering from chronic pain than persons in the age group 16–24 years . Compared with married persons , divorced or separated persons had 1.5 higher odds of chronic pain . Odds for chronic pain were 1.9 higher among those with an education of less than 10 years compared with individuals with an education of 13 years or more . During a 14‐day period reporters of chronic pain had an average of 0.8 days ( range 0–10 ) lost due to illness compared with an average of 0.4 days ( range 0–10 ) for the control group ( CG ) ( Odds Ratio ( OR ) ) 2.0 ) . Persons with a job which required high physical strain were more likely to report chronic pain compared with those with a sedentary job ( OR 2.2 ) . The odds of quitting one 's job because of ill health were seven times higher among people belonging to the PG . A strong association between chronic pain and poor self‐rated health was also demonstrated . The PG had twice as many contacts with various health professionals compared with the CG , and the health care system was , on average , utilised 25 % more ( overall contacts ) by the PG than by the general population . Among the persons in the PG , 33 % were not satisfied with the examinations carried out in connection with their pain condition and 40 % were not satisfied with the treatment offered . Nearly 130,000 adults , corresponding to 3 % of the Danish population , use opioids on a regular basis . Opioids are used by 12 % of the PG & NA ; Myofascial trigger points ( TrPs ) have been clinical ly described as discrete areas of muscle tenderness presenting in taut b and s of skeletal muscle . Using well‐defined clinical criteria , prior investigations have demonstrated interrater reliability in the diagnosis of TrPs within a given muscle . No reports exist , however , with respect to the precision with which experienced clinicians can determine the anatomic locations of TrPs within a muscle . This paper details a study wherein four trained clinicians achieved statistically significant reliability ( see below ) in estimating the precise locations of latent TrPs in the trapezius muscle of volunteer subjects ( n=20 ) . To do so , the clinicians trained extensively together prior to the study . The precise anatomic location of each subject 's primary TrP was measured in a blinded fashion using a 3 dimensional ( 3‐D ) camera system . Use of this measurement system permitted the anatomic co‐ordinates of each TrP to be located without providing feedback to subsequent clinicians . The clinicians each used a pressure algometer along with patient feedback to document the sensitivity of each suspected TrP site , however unlike routine clinical practice , the algometry was performed with a double‐blinded approach hence the results were only examined post‐hoc . At the time of data collection ( algometry readings unknown ) , 16 of the 20 subjects were judged to present with a latent TrP. Subsequently , when subjected to a criterion pressure threshold value of < 3.0 kg.cm−2 , 12 of these TrPs were classified as being clinical ly sensitive . To assess the 3‐D measurement precision , and the reliability of the TrP estimates , statistical measures of the SEM and the Generalizability coefficient ( G‐coeff ) were determined for all suspected TrP sites in the superior‐inferior , medial‐lateral and anterior‐posterior directions . The best results were determined by pooling the measurements of all 4 clinicians , however , based upon exceeding a criterion reliability threshold of 80 % , the use of just two testers was found to produce reliable results . The two‐tester condition yielded a precision of 7.5 , 7.6 and 6.5 mm ( SEM ) with reliability ( G‐coeff ) of 0.92 , 0.86 and 0.83 , respectively . Given the double‐blinded methodology , the use of pressure algometry was also found to demonstrate internal validity . The algometer responses associated with TrP estimates varied inversely with respect to the clinical group 's reliability in identify the TrP locations . To summarize , for the trapezius muscle , this study demonstrates that two trained examiners can reliably localize latent TrPs with a precision that essentially approaches the physical dimensions of the clinician 's own fingertips . Finally , it should be recognized that the ability to precisely document TrP location appears critical to the success of future studies that may be design ed to investigate the etiology and pathogenesis of this commonly diagnosed clinical disorder The purpose of this study was to determine the intertester reliability of assessment s of the presence of trigger points in the region of the lumbar spine of patients with low back pain ( LBP ) . A total of six trigger points described by Travell and Simons were studied . The trigger point examination procedures described by Travell and Simons were used by 12 physical therapists . R and omly paired therapists examined 50 patients for 197 trigger points . The Kappa coefficient , percent agreement , the observed proportion of positive agreement ( Ppos ) , and the observed proportion of negative agreement ( Pneg ) were used to describe reliability . Kappa values ranged from .29 to .38 . Percent agreement ranged from 76 % to 79 % . Ppos ranged from .43 to .52 . The low Kappa and Ppos values suggest different therapists are unable to reliably determine when a trigger point is present in a patient with LBP . This study suggests the usefulness of examining for the presence of trigger points in patients with LBP should be question ed OBJECTIVES To determine the interexaminer reliability of palpation of three characteristics of trigger points ( taut b and , local twitch response , and referred pain ) in patients with subacute low back pain , to determine whether training in palpation would improve reliability , and whether there was a difference between the physiatric and chiropractic physicians . DESIGN Reliability study . SETTING Whittier Health Campus , Los Angeles College of Chiropractic . PARTICIPANTS Twenty-six nonsymptomatic individuals and 26 individuals with subacute low back pain . INTERVENTION Twenty muscles per individual were first palpated by an expert and then r and omly by four physician examiners . MAIN OUTCOME MEASURES Palpation findings . RESULTS Kappa scores for palpation of taut b and s , local twitch responses , and referred pain were .215 , .123 , and .342 , respectively , between the expert and the trained examiners , and .050 , .118 , and .326 , respectively , between the expert and the untrained examiners . Kappa scores for agreement for palpation of taut b and s , twitch responses , and referred pain were .108 , -.001 , and .435 , respectively , among the nonexpert , trained examiners , and -.019 , .022 , and .320 , respectively , among the nonexpert , untrained examiners . CONCLUSIONS Among nonexpert physicians , physiatric or chiropractic , trigger point palpation is not reliable for detecting taut b and and local twitch response , and only marginally reliable for referred pain after training The presence of a trigger point is essential to the myofascial pain syndrome . This study centres on identifying clearer criteria for the presence of trigger points in the quadratus lumborum and gluteus medius muscle by investigating the occurrence and inter-rater reliability of trigger point symptoms . Using the symptoms and signs as described by Simons ' 1990 definition and two other former sets of criteria , 61 non-specific low back pain patients and 63 controls were examined in general practice by 5 observers , working in pairs . From the two major criteria of Simons ' 1990 definition only ' localized tenderness ' has good discriminative ability and inter-rater reliability ( kappa > 0.5 ) . This study does not find proof for the clinical usefulness of ' referred pain ' , which has neither of these two abilities . The criteria ' jump sign ' and ' recognition ' , on the condition that localized tenderness is present , also have good discriminative ability and inter-rater reliability . Trigger points defined by the criteria found eligible in this study allow significant distinction between non-specific low back pain patients and controls . This is not the case with trigger points defined by Simons ' 1990 criteria . Concerning reliability there is also a significant difference between the two different criteria sets . This study suggests that the clinical usefulness of trigger points is increased when localized tenderness and the presence of either jump sign or patient 's recognition of his pain complaint are used as criteria for the presence of trigger points in the M. quadratus lumborum and the M. gluteus medius Objectives : To investigate the test-retest reliability of the following clinical diagnostic characteristics of myofascial trigger points : taut b and , spot tenderness , jump sign , pain recognition , referred pain and local twitch responses ( LTRs ) . Design : Test-retest reliability study . Setting : This study was undertaken in an outpatient physiotherapy department . Subjects : Fifty-eight patients ( 31 males and 27 females ) with rotator cuff tendonitis were recruited into this study . Intervention : Rotator cuff muscles were assessed by an expert for the presence or absence of the main clinical diagnostic characteristics of trigger point assessment . The process was then repeated three days later by the same expert . Main measures : Outcomes included the presence or absence of : a taut b and , spot tenderness , jump sign , pain recognition , referred pain and LTRs . Results : Kappa values between testing situations for the taut b and , spot tenderness , jump sign and pain recognition were 1 . Kappa scores for referred pain ranged between 0.79 and 0.88 and for the local twitch response between 0.75 and 1 depending on the muscles under investigation . Conclusions : The presence or absence of the taut b and , spot tenderness , jump sign and pain recognition was highly reliable between sessions . Referred pain and local twitch response reliability varied depending on the muscle being studied Abstract The myofascial trigger point ( MTrP ) is the hallmark physical finding of the myofascial pain syndrome ( MPS ) . The MTrP itself is characterized by distinctive physical features that include a tender point in a taut b and of muscle , a local twitch response ( LTR ) to mechanical stimulation , a pain referral pattern characteristic of trigger points of specific areas in each muscle , and the reproduction of the patient 's usual pain . No prior study has demonstrated that these physical features are reproducible among different examiners , thereby establishing the reliability of the physical examination in the diagnosis of the MPS . This paper reports an initial attempt to establish the interrater reliability of the trigger point examination that failed , and a second study by the same examiners that included a training period and that successfully established interrater reliability in the diagnosis of the MTrP. The study also showed that the interrater reliability of different features varies , the LTR being the most difficult , and that the interrater reliability of the identification of MTrP features among different muscles also varies Simons DG , Hong C-Z , Simons LS : Endplate potentials are common to midfiber myofacial trigger points . Am J Phys Med Rehabil 2002;81:212–222 . Objective To compare the prevalence of motor endplate potentials ( noise and spikes ) in active central myofascial trigger points , endplate zones , and taut b and s of skeletal muscle to assess the specificity of endplate potentials to myofascial trigger points . Design This nonr and omized , unblinded needle examination of myofascial trigger points compares the prevalence of three forms of endplate potentials at one test site and two control sites in 11 muscles of 10 subjects . The endplate zone was independently determined electrically . Active central myofascial trigger points were identified by spot tenderness in a palpable taut b and of muscle , a local twitch response to snapping palpation , and the subject ’s recognition of pain elicited by pressure on the tender spot . Results Endplate noise without spikes occurred in all 11 muscles at trigger-point sites , in four muscles at endplate zone sites outside of trigger points ( P = 0.024 ) , and did not occur in taut b and sites outside of an endplate zone ( P = 0.000034 ) . Conclusion Endplate noise was significantly more prevalent in myofascial trigger points than in sites that were outside of a trigger point but still within the endplate zone . Endplate noise seems to be characteristic of , but is not restricted to , the region of a myofascial trigger point & NA ; Temporom and ibular disorders ( TMD ) diagnoses can be viewed as the most useful clinical summary for classifying subtypes of TMD . The Research Diagnostic Criteria for TMD ( RDC/TMD ) is the most widely used TMD diagnostic system for conducting clinical research . It has been translated into 18 language s and is used by a consortium of 45 RDC/TMD‐based international research ers . While reliability of RDC/TMD signs and symptoms of TMD has been amply reported , the reliability of RDC/TMD diagnoses has not . The aim of the study was to determine the reliability of clinical TMD diagnoses using st and ardized methods and operational definitions contained in the Research Diagnostic Criteria for Temporom and ibular Disorders ( RDC/TMD ) . Data came from reliability assessment trials conducted at 10 international clinical centers , involving 30 clinical examiners assessing 230 subjects .  Intraclass correlation coefficients ( ICC ) were calculated to characterize the reliability . The reliability of the diagnoses was fair to good . Median ICCs for the diagnoses myofascial pain with and without limited opening were 0.51 and 0.60 , respectively . Median ICC for arthralgia was 0.47 and 0.61 for disc displacement with reduction . RDC/TMD diagnoses of disc displacement without reduction , osteoarthritis and osteoarthrosis were not prevalent enough to calculate ICC 's , but percent agreement was always > 95 % . The reliability of diagnostic classification improved when diagnoses were grouped into pain versus non‐pain diagnoses ( ICC=0.72 ) and for detecting any diagnosis versus no diagnosis ( ICC=0.78 ) . In clinical decision‐making and research , arriving at a reliable diagnosis is critical in establishing a clinical condition and a rational approach to treatment . The RDC/TMD demonstrates sufficiently high reliability for the most common TMD diagnoses , supporting its use in clinical research and decision making & NA ; Although neck pain is a common source of disability , little is known about its incidence and course . We conducted a population ‐based cohort study of 1100 r and omly selected Saskatchewan adults to determine the annual incidence of neck pain and describe its course . Subjects were initially surveyed by mail in September 1995 and followed‐up 6 and 12 months later . The age and gender st and ardized annual incidence of neck pain is 14.6 % ( 95 % confidence interval : 11.3 , 17.9 ) . Each year , 0.6 % ( 95 % confidence interval : 0.0–1.1 ) of the population develops disabling neck pain . The annual rate of resolution of neck pain is 36.6 % ( 95 % confidence interval : 32.7 , 40.5 ) and another 32.7 % ( 95 % confidence interval : 25.5 , 39.9 ) report improvement . Among subjects with prevalent neck pain at baseline , 37.3 % ( 95 % confidence interval : 33.4 , 41.2 ) report persistent problems and 9.9 % ( 95 % confidence interval : 7.4 , 12.5 ) experience an aggravation during follow‐up . Finally , 22.8 % ( 95 % confidence interval : 16.4 , 29.3 ) of those with prevalent neck pain at baseline report a recurrent episode . Women are more likely than men to develop neck pain ( incidence rate ratio=1.67 , 95 % confidence interval 1.08–2.60 ) ; more likely to suffer from persistent neck problems ( incidence rate ratio=1.19 , 95 % confidence interval 1.03–1.38 ) and less likely to experience resolution ( incidence rate ratio=0.75 , 95 % confidence interval 0.63–0.88 ) . Neck pain is a disabling condition with a course marked by periods of remission and exacerbation . Contrary to prior belief , most individuals with neck pain do not experience complete resolution of their symptoms and disability Abstract The aim of this study was to investigate the reliability between different examiners when using the axis I of the Research Diagnostic Criteria for Temporom and ibular Disorders ( RDC/TMD ) . The hypothesis was that the st and ardized RDC/TMD examination protocol enables calibrated examiners to evaluate all examination items reliably . After calibration training by the RDC/TMD calibration team including the calibration of palpation pressure and the performance of the st and ardized examination protocol , four examiners , blinded to the patients ’ medical histories examined 24 subjects in a r and omized sequence . One experienced examiner was the st and ard ( hierarchical calibration ) . The recorded measurements strictly followed the RDC/TMD . Intraclass correlation coefficients ( ICC ) , bias and precision were calculated to estimate interrater reliability . Acceptable ( 0.75≥ICC>0.4 ) to excellent ( ICC>0.75 ) reliability was found for 20 of the 23 ( 87 % ) examinations . Only sub-retrom and ibular muscle palpation and joint sound vibration recordings on lateral excursion showed poor- results ( ICC≤0.4 ) . The RDC/TMD examination protocol enables calibrated examiners to perform most ( 87 % ) examination items with satisfactory reliability . Therefore multi-site studies based on the RDC/TMD examination protocol may become feasible , keeping in mind the unsatisfactory reliability of 13 % of the items ( clicking during laterotrusion to the ipsilateral side , palpation of the posterior and subm and ibular region ) & NA ; In a postal survey , we asked 1009 r and omly chosen individuals , age 18–84 , about their pain problems . The pain prevalence depended on what types of questions were asked . Any pain or discomfort , including even a problem of short duration , was reported by 66 % of those question ed . Forty percent reported ‘ obvious pain ’ ( pain which affected them ‘ to quite a high degree ’ or more and was ‘ like being stiff after exercise ’ or worse ) lasting more than 6 months . Pain problems of more than 6 months duration were reported far more often than short‐lasting problems . Continuous or nearly continuous pain problems were reported as frequently as problems recurring regularly or irregularly . Pains in the neck , shoulders , arms , lower back and legs were most frequent . The prevalence of ‘ obvious pain ’ in these localizations was 15–20 % . Pain was reported most frequently in the age group 45–64 , where the prevalence of ‘ obvious pain ’ was 50 % among males as well as females . Over 65 years of age the prevalence was less OBJECTIVES To develop a structured physical examination protocol that identifies common biomechanical and soft-tissue abnormalities for older adults with chronic low back pain ( CLBP ) that can be used as a triage tool for healthcare providers and to test the interobserver reliability and discriminant validity of this protocol . DESIGN Cross-sectional survey and examination . SETTING Older adult pain clinic . PARTICIPANTS One hundred eleven community-dwelling adults aged 60 and older with CLBP and 20 who were pain-free . MEASUREMENTS Clinical history for demographics , pain duration , previous lumbar surgery or advanced imaging , neurogenic claudication , and imaging clinical ly serious symptoms . Physical examination for scoliosis , functional leg length discrepancy , pain with lumbar movement , myofascial pain ( paralumbar , piriformis , tensor fasciae latae ( TFL ) ) , regional bone pain ( sacroiliac joint ( SIJ ) , hip , vertebral body ) , and fibromyalgia . RESULTS Scoliosis was prevalent in those with ( 77.5 % ) and without pain ( 60.0 % ) , but prevalence of SIJ pain ( 84 % vs 5 % ) , fibromyalgia tender points ( 19 % vs 0 % ) , myofascial pain ( 96 % vs 10 % ) , and hip pain ( 48 % vs 0 % ) was significantly different between groups ( P < .001 ) . Interrater reliability was excellent for SIJ pain ( 0.81 ) , number of fibromyalgia tender points ( 0.84 ) , and TFL pain ( 0.81 ) ; good for scoliosis ( 0.43 ) , kyphosis ( 0.66 ) , lumbar movement pain ( 0.75 ) , piriformis pain ( 0.71 ) , and hip disease by internal rotation ( 0.56 ) ; and marginal for leg length ( 0.00 ) and paravertebral pain ( 0.39 ) . CONCLUSION Biomechanical and soft tissue pathologies are common in older adults with CLBP , and many can be assessed reliably using a brief physical examination . Their recognition may save unnecessary healthcare expenditure and patient suffering & NA ; Data from the World Health Organization 's study of psychological problems in general health care were used to examine the course of persistent pain syndromes among primary care patients . Across 15 sites in 14 countries , 3197 r and omly selected primary care patients completed baseline and 12‐month follow‐up assessment s  of pain , other somatic symptoms , and anxiety and depressive disorders  ( the Composite International Diagnostic Interview ) , and an assessment of occupational role disability  ( the Social Disability Schedule ) . Of patients with a persistent pain condition at baseline , 49 % had not recovered 12 months later . The probability of non‐recovery varied significantly across study centers and was significantly associated with the number of pain sites at baseline . After adjustment for age , sex , and study center , baseline anxiety or depressive disorder did not predict non‐recovery of persistent pain . Among those without a persistent pain disorder at baseline , the rate of onset was 8.8 % with a significant variability in risk across centers . The baseline characteristics predicting the onset of persistent pain disorder were psychological disorder , poor self‐rated health , and occupational role disability . A persistent pain disorder at baseline predicted the onset of a psychological disorder to the same degree that a baseline psychological disorder predicted the subsequent onset of persistent pain . Persistent pain conditions are common among primary care patients , and the probability of resolution over 12 months is approximately 50 % . We found a strong and symmetrical relationship between persistent pain and psychological disorder . Impairment of daily activities appears to be a central component of that relationship & NA ; The overall population impact of chronic pain on work performance has been underestimated as it has often been described in terms of work‐related absence , excluding more subtle effects that chronic pain may have on the ability to work effectively . Additionally , most studies have focussed on occupational and /or patient cohorts and treatment seeking , rather than sampling from the general population . We undertook a population ‐based r and om digit dialling computer‐assisted telephone survey with participants r and omly selected within households in order to measure the impact of chronic  pain on work performance . In addition , we measured the association between pain‐related disability and litigation . The study took place in Northern Sydney Health Area , a geographically defined urban area of New South Wales , Australia , and included 484 adults aged 18 or over with chronic pain . The response rate was 73.4 % .  Working with pain was more common ( on an average 83.8 days in 6 months ) than lost work days due to pain ( 4.5 days ) among chronic pain participants in full‐time or part‐time employment . When both lost work days and reduced‐effectiveness work days were summed , an average of 16.4 lost work day equivalents occurred in a 6‐month period , approximately three times the average number of lost work days . In multiple logistic regression modelling with pain‐related disability as the dependent variable , past or present pain‐related litigation had the strongest association ( odds ratio (OR)=3.59 , P=0.001 ) . In conclusion , chronic pain had a larger impact on work performance than has previously been recognised , related to reduced performance while working with pain . A significant proportion were able to work effectively with pain , suggesting that complete relief of pain may not be an essential therapeutic target . Litigation ( principally work‐related ) for chronic pain was strongly associated with higher levels of pain‐related disability , even after taking into account other factors associated with poor functional outcomes & NA ; This study reports chronic pain prevalence in a r and omly selected sample of the adult Australian population . Data were collected by Computer‐Assisted Telephone Interview ( CATI ) using r and omly generated telephone numbers and a two‐stage stratified sample design . Chronic pain was defined as pain experienced every day for three months in the six months prior to interview . There were 17,543 completed interviews ( response rate=70.8 % ) . Chronic pain was reported by 17.1 % of males and 20.0 % of females . For males , prevalence peaked at 27.0 % in the 65–69 year age group and for females , prevalence peaked at 31.0 % in the oldest age group ( 80–84 years ) . Having chronic pain was significantly associated with older age , female gender , lower levels of completed education , and not having private health insurance ; it was also strongly associated with receiving a disability benefit ( adjusted OR=3.89 , P<0.001 ) or unemployment benefit ( adjusted OR=1.99 , P<0.001 ) ; being unemployed for health reasons ( adjusted OR=6.41 , P<0.001 ) ; having poor self‐rated health ( adjusted OR=7.24 , P<0.001 ) ; and high levels of psychological distress ( adjusted OR=3.16 , P<0.001 ) . Eleven per cent of males and 13.5 % of females in the survey reported some degree of interference with daily activities caused by their pain . Prevalence of interference was highest in the 55–59 year age group in both males ( 17.2 % ) and females ( 19.7 % ) . Younger respondents with chronic pain were proportionately most likely to report interference due to pain , affecting 84.3 % of females and 75.9 % of males aged 20–24 years with chronic pain . Within the subgroup of respondents reporting chronic pain , the presence of interference with daily activities caused by pain was significantly associated with younger age ; female gender ; and not having private health insurance . There were strong associations between having interfering chronic pain and receiving disability benefits ( adjusted OR=3.31 , P<0.001 ) or being unemployed due to health reasons ( adjusted OR=7.94 , P<0.001 , respectively ) . The results show that chronic pain impacts upon a large proportion of the adult Australian population , including the working age population , and is strongly associated with markers of social disadvantage
target: On the basis of the limited number of studies available , and significant problems with their design , reporting , statistical integrity , and clinical applicability , physical examination can not currently be recommended as a reliable test for the diagnosis of trigger points .
background: BACKGROUND Trigger points are promoted as an important cause of musculoskeletal pain .
  There is no accepted reference st and ard for the diagnosis of trigger points , and data on the reliability of physical examination for trigger points are conflicting .
  OBJECTIVES To systematic ally review the literature on the reliability of physical examination for the diagnosis of trigger points .