it is classically indicated in cases of degenerative processes and sequelae of inflammatory diseases , and has been greatly developed in orthopedic practice . the indications , which initially presented only functional limitations , are becoming increasingly broadened as a result of the availability of prosthetic materials of better quality and the growing familiarization of medical teams with the tools used . consistent with this trend , we started carrying out total arthroplasty for a few patients with painful ankylosis of the knee several years ago . these patients were also presented with the alternative of arthrodesis of the knee as a therapeutic procedure that could reduce the pain , but not the severe functional limitation . a select group of patients was presented with the therapeutic option of total arthroplasty of the knee to reestablish movement and significantly reduce pain , followed with arthrodesis in the event of arthroplasty failure . some of the patients accepted the challenge and , in the present study , we report the clinical course of the first nine of these cases who have now been followed up for at least five years . over a minimum period of five years , we studied the clinical course of nine patients with ankylosis in their knees who underwent total arthroplasty for treatment . at their initial assessment , these nine patients presented pain and joint limitation that allowed less than five degrees of movement . the patients characteristics and the initial diagnoses are reported in table 1 . all patients with sequelae from fractures had suffered joint fractures that had been treated surgically . they had all undergone at least two operations to improve their range of motion , without success . three patients had experienced postoperative infections : two following surgery for ligament repair and one following surgery to realign the extensor apparatus . these three patients with previous infection were declared as surgically fit for total arthroplasty after assessment by an infectologist based on c - reactive protein assays and scintigraphy with radiolabeled leukocytes . the only case of reflex sympathetic dystrophy occurred following arthroscopy to treat  chondromalacia patellar  . this patient had undergone nine surgical attempts to improve her range of motion without success . six patients presented with permanent deformities and ankylosis , which they had been experiencing for 4.8 years , on average . table 2 describes the deformities observed at the time of preoperative assessment , the clinical course ( duration ) of the ankylosis , and the assessment system score used by the hospital for special surgery ( hss)1 , taking into account the preoperative functional score obtained for the knee . the patients were informed that there would be two possibilities for treating their ankylosis : - arthrodesis of the knee - total arthroplasty , with the risk of short durability and the need for arthrodesis in the event of arthroplasty failure . the nine patients signed a consent statement to undergo total arthroplasty . in all cases , the access route consisted of detachment of the anterior tuberosity of the tibia with bone fragments , followed by osteotomy ( figure 1 ) . after detaching and pushing back all of the extensor apparatus proximally , the joint was approached and the ankylosis was released . in all cases , we were able to identify the level of the joint interline . with the knee flexed at 90 degrees , the level of the proximal cut was limited to a line perpendicular to the axis of the tibia , at the level of the proximal epiphysis of the fibula . after resecting the tibial fragment , we approached the femur using an intramedullary guide and a resection level close to the bi - epicondyle line . after the cuts were prepared , we introduced the tibial and femoral specimens and performed flexion - extension with the test pieces made of polyethylene . we considered the thickness of the polyethylene to be good when flexion - extension occurred without any pressure . we attached the anterior tuberosity of the tibia using three or four wire loops , with the knee flexed at 60 degrees ( figure 2 ) . in all cases , we used primary prostheses without posterior stabilization , and without patella replacement ( figure 3 ) . during the postoperative treatment , strengthening and stretching of the leg musculature were performed , the joint was mobilized to gain range of motion , and cryotherapy was applied for pain relief and to control the inflammatory process . the patients were followed up by means of weekly visits , during which radiography and functional assessments were carried out . the mean age was 36 years , and the right side was more affected than the left ( six of the nine patients ) . all nine patients presented significant reductions in pain following the surgery , such that five reported only mild or occasional pain , and four described moderate pain upon exertion . table 3 summarizes the results , including the current degree of deformity , the degree of movement obtained after a minimum of five years of follow - up , and the hss assessment ( 1 ) . the complications indicated with an asterisk were two cases of late infection . in the first case , the ankylosis was a sequela of a fracture without prior infection and , in the second case , the patient had experienced an infection following ligament repair of the knee . both of these cases of infection occurred during the second year of follow - up . the first case required surgical cleaning , placement of a spacer for six weeks and subsequent replacement with a revision prosthesis , and the use of a flap from the medial gastrocnemius . this patient has now been followed for six years following the revision , and no new symptoms resulting from the infection have been presented . in the second case , surgical cleaning was performed with the use of a spacer for eight weeks , followed by revision prosthesis . this patient has now undergone five years of follow - up following the revision and is well , without any symptoms of infection . ankylosis of the knee is a severe incapacity that causes significant functional limitation , especially when associated with pain . using total arthroplasty for this group of patients , we sought to reduce the pain and simultaneously improve their knee movement . in our sample of young patients , the severe limitation was reflected in their low hss scores.1 we believe that their young ages were not contraindications , because of the severity of their limitation . other authors who have described their experiences in dealing with severe joint limitations have also carried out arthroplasty in young patients . schurman et al.2 described arthroplasty of an ankylosed knee in the case of a 24-year - old patient . given the young age of these patients and the possible need for future revision , we sought to perform arthroplasty in the least aggressive manner possible . for this , we used prostheses without posterior stabilization , and we did not replace the patella , since there was less bone resection . aglietti et al.3 described their experience in treating knees with severe joint limitations using prostheses with posterior stabilization . we believe that , although the bone resection and consequent ligament resection are extensive in cases of ankylosis , the anteroposterior stability in this group of patients is less important , due to the limitation of movement that consistently remains . we did not use continuous movement equipment , since we judged that it was not necessary to detect any adherence or movement restriction within the first 72 hours , since we judged that it was necessary to detect any adherence or movement restriction within the first 72 hours . if any limitations were present , the intensity of the manipulation could have been immediately increased . manipulation of postoperative joint limitations should be performed as early as possible , as suggested by yercan et al.4 improved movement was observed in all of our patients , although a limitation of five degrees of extension occurred in four patients , and the mean flexion gain was 65. naranja et al.5 described a mean flexion gain of 62 in a multicenter study . rajgopal et al.6 reported a mean flexion gain of 61 in 84 knees of 54 patients who presented severe joint limitation . a significant reduction in pain was observed in all our patients , in addition to gains in movement . however , we were unable to reestablish normality for any of the cases . from a two - year follow - up of a series of nine cases similar to ours , bradley et al.7 considered their results to be satisfactory with regard to reductions in pain and partial gains in movement . rajgopal et al.6 presented a series of 84 knees among 53 patients with severe joint limitation . after a mean follow - up of nine years , they considered their results to be good because their patients experienced reduced pain and improved quality of life . both were due to infections , and one of our patients developed ankylosis as a consequence of infection . kim et al.8 performed arthroplasty in 16 patients with ankylosis of the knee following pyogenic infection or tuberculosis . in most of those cases , the results were satisfactory , with postoperative infection occurring in just two cases . in a multicenter study of 35 patients who underwent total arthroplasty of their ankylosed knees , naranja et al.5 reported an early complication frequency of 24% and a major complication frequency of 35% . there is no doubt that arthroplasty of ankylosed knees is a risky procedure , and this limitation must be clearly laid out for potential patients . nevertheless , the possibility of gains in movement and significant reductions in pain may compensate for the risks . the evident shortcoming of the present study is our small number of cases , which precluded the ability to obtain definitive conclusions . in the event of complete failure in the attempt to perform arthroplasty , we would have performed arthrodesis , the only procedural indication for this group of patients other than arthroplasty . however , based on the latest follow - up , there had been no need to perform arthrodesis for any of our patients .
objectiveto present nine patients with ankylosis in their knees that were submitted to a total arthroplasty to lessen their pain and improve their functional limitation . for these patients , 
 arthrodesis remained a possibility in the event of arthroplasty failure.introductionankylosis of the knee is a severe functional limitation that becomes worse when pain is present . 
 arthrodesis of the knee is a classical indication for such patients , since it resolves the pain ; however , the severe functional limitation remains.methodsin the present study , we evaluated the clinical course of nine patients who underwent total arthroplasty of the knee , and were followed up for at least five years.resultsthe results demonstrate that all of the patients experienced a significant reduction in pain and some improvement in the degree of knee flexion and extension.conclusionbased on the latest follow - up , there has been no need to perform arthrodesis for any of our patients , showing that a total arthroplasty could be a option for treatment in knee ankylosis .