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A single case of massive necrosis of soft tissues was seen one year after insertion of a total knee hinged prosthesis. The authors believe that this was due to hypersensitivity to Cobalt. The prosthesis had to be removed and the knee fused.
The midterm results of primary posterior cruciate ligament-retaining, minimally conforming, cemented modular total knee arthroplasties using the Genesis I prosthesis in 110 knees in 72 patients were reviewed. Patients were evaluated at a mean follow-up of 7.3 years by Knee Society pain and functional scores, radiographic and survivorship analysis, and Western Ontario and MacMaster Universities Osteoarthritis Index (WOMAC) health status questionnaire. Range of motion increased from an average of 96.3 degrees to 112.5 degrees. Knee Society pain and functional scores increased from preoperative averages of 55 and 44 to 92 and 88, respectively. There were 91 excellent, 16 good, 1 fair, and 2 poor results. WOMAC scores were increased significantly in each subcategory examined (pain, stiffness, and physical function). Kaplan-Meier survivorship was 97% at 10 years. An increase in loosening as a result of eccentric stress concentration secondary to the nonconforming design of this prosthesis, theoretically a matter of some clinical concern, was not shown in this investigation.
Spin-out of mobile-bearing knees is a significant early complication of mobile-bearing total knee arthroplasty. Dislocation of the cam-post mechanism of fixed-bearing posterior-stabilized knees occurs more rarely. We have observed an unusual case of dislocation of posterior-stabilized rotating-platform total knee arthroplasty, which has both a cam-post mechanism and rotating platform. A 65-year-old man with knee osteoarthritis and cervical spondylotic myelopathy underwent total knee arthroplasty using a mobile-bearing prosthesis. The dislocation, which occurred 4 days postoperatively, could not be reduced by closed manipulation. However, spontaneous reduction occurred 6 days after the dislocation, which did not recur. A gap mismatch or trapezoidal-shaped gaps may lead to dislocation or spin-out of the bearing insert. This case illustrates that dislocation of a posterior-stabilized mobile-bearing total knee arthroplasty can occur, and both quadriceps deficiency and ligament laxity may contribute to the risk of dislocation.
Lower limb prostheses produced so far do not replace the function of the musculature, which provides the necessary amount and the proper distribution of energy to the ambulatory mechanism. Provision of external power to lower limb prostheses has been hindered by the fact that the large amount of energy needed at a lower limb necessitates the use of external power sources of unacceptably high mass and volume. Self energized mechanisms offer a promising alternative to the problem. Normally a large part of energy output during locomotion appears at the ankle joint. It seems therefore desirable to develop an above-knee prosthesis featuring active plantar-flexion at the ankle. Energy may be offered by a self energized system. The system, described here, accumulates energy during the passive movements of the knee and ankle joints and stores it for later use at the ankle.
Three types of patellar complication following total knee replacement with a Freeman-I.C.L.H. prosthesis have been studied. They are: 1) Pain despite a satisfactory position of the patella. 2) Patella fractures and 3) Lateral displacement. Pain in spite of a satisfactory position of the patella occurred in 15 p. 100 of cases. The incidence of this complication was considerably diminished by the use of a patellar implant. The use of a patellar implant did not result in any specific morbidity. Five fractures of the patella were seen, three of them without displacement. Lateral displacement of the patella were seen in 5 p. 100 of cases resulting in instability of the knee and a higher risk of loosening of the tibial component. The authors propose a new type of patellar implant stabilized by a rail.
A retrospective study of 88 of 117 kinematic total knee prostheses was carried out at the Department of Orthopaedics, University Clinic, Innsbruck. In 71 cases the clinical and functional score of the knee Society was applied. Radiographs were taken under fluoroscopic control. In 3 cases, the need for revision surgery was already obvious. A slight varus angle of 2.1 degrees became apparent. Flexion contracture showed a correlation with the inclination of the femoral component. Radiolucencies of the tibial component showed up in cases with a reduced tibial angle. Radiolucencies of the patella component correlated with lateral subluxation.
This is a case report of a Cloutier total knee arthroplasty that was removed from an obese, large, 66-year-old man three years after implantation because of aseptic loosening. At surgery there was a thickened black synovium and black cystic areas in the exposed bone. The articulating surfaces of the tibial component, which is made from Poly Two (a carbon polyethylene composite), were grossly abraded, and the supporting metal tray was broken in two. The femoral component showed signs of abnormal wear at the places where it was articulating with the displaced tibial component. The tissues showed a granulomatous reaction with marrow fibrosis and cystic destruction of bone. It is postulated that aseptic loosening was accelerated by a granulomatous response to overload, abrasion, and local dissemination of particles.
We have reviewed 105 Liverpool Mark II knee replacements in 71 patients to assess survival and long-term results. Assessment was both clinical and radiological, using a modification of the British Orthopaedic Association knee function assessment chart, and analysis was by the survivorship method as advocated by Tew and Waugh. The follow-up period was between 13 and 113 months with 42 prostheses being in situ for over six years. Eight knees (7.6%) have been revised or arthrodesed because of infection or loosening, giving a cumulative success rate of 89% after seven years based on prosthesis survival alone. Of the remaining knees, 71.1% were either free of pain or caused only minimal pain. The cumulative success rate as judged by the stricter criteria of the prosthesis being in situ and causing little or no pain suggested a 50% survival between 73 and 96 months. Most patients (77.3%) were enthusiastic or satisfied with their results. Complications included deep wound infection (8.6%), and loosening which needed further surgery (11.4%).
We implanted the total arthroplasty knee or TACK prosthesis in 40 patients with degenerative osteoarthritis. We used the same surgical technique in all patients. Full extension and flexion more than 90 degrees were achieved in all 40 knees. All patients obtained a HSS score of more than 88 points. The results confirm that the TACK prosthesis provides excellent results in patients with degenerative osteoarthritis if there is no significant bone loss, serious ligament laxity or extensive deformation.
In our clinical the GSB-prosthesis has proved to be a good therapeutic concept. In 1988 we controlled 230 patients who had got GSB-prostheses in the years 1979-1987. The average age of our patients was 75 years. Most times surgery had been done because of idiopathic osteoarthrosis, rarely because of post-traumatic or rheumatoid arthritis. Indications for surgery were usually severe pain, limited range of movement and deformities of the knee joint. In the beginning of the studied period we had implanted GSB-type I-prostheses, later we had implanted GSB-type II-prostheses with or without femoropatellar surface. We achieved good results in pain reduction and in range of movement. However the major complications were caused by the patella. These patients had problems at climbing stairs, pain at the beginning of movements and at getting up from chairs. They presented with increased pain sensitivity at the tip of the patella and to friction of the patella. Regular radiological findings were severe destructions or fractures of the upper patellar pole. These problems led in 40 cases (17% of our cases) to reoperations until 1988 (At all we reoperated 50 times because some patients needed additional reoperations). According to our studies results there will be a need for reoperations in about 50 other cases. We discuss the following reasons for this high rate of severe patellar complications demanding re-surgery: 1. Localisation of the patella: according to our studies the patella is frequently dranged cranially, seldom laterally. 2. Often we found an internal rotation of the tibia against the femur.(ABSTRACT TRUNCATED AT 250 WORDS)
We studied the first 100 consecutive patients (125 knees) to undergo knee arthroplasty with the original total condylar-I prosthesis for either osteoarthritis or osteonecrosis on the Knee Service at The Hospital for Special Surgery. They were followed for an average of 6.6 years (range, five to nine years), which is the longest follow-up of a total knee prosthesis that is still widely used in its original and unmodified form. At five to nine years of follow-up, eleven patients (fourteen knees) were dead and ten patients (eleven knees) could not be traced, leaving 100 knees (seventy-nine patients) for clinical evaluation. This included one knee from which the prosthesis was removed for sepsis at six months, four that were revised for pain, and two that were revised because of subluxation. Two patients had a loose tibial component. Sixty-four knees were rated as excellent and twenty-seven were rated as good. There were two fair and seven poor results. Detailed radiographic evaluation of the 100 knees showed that only minimum changes in the varus or valgus alignment or the fixation of the prosthetic components had occurred with time. At follow-up, 41 per cent of the tibial components showed some evidence of radiolucency, although with the exception of the two loose components just mentioned there were no complete or circumferential radiolucent lines. Most radiolucencies were present by the end of the first postoperative year, and in 81 per cent of the knees there was no further change. Although a special attempt was made to determine any evidence of wear of the polyethylene tibial component, we were unable to demonstrate unequivocal wear in any knee. Our experience had led us to conclude that the long-term success of current total knee designs will probably not be significantly affected by polyethylene wear or loss of component fixation. The majority of failures in our series were attributed to errors in surgical technique.
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16 early deaths (within 24 hours) were observed after 758 knee joint replacements. In eight instances the patient died during the operation, and the other eight few hours later. The author discussed several possible causes: toxicity of the monomere, fat embolism hyperpressure in the medullary canal, hemorrhage. Several per and post operative precautions are recomanded.
OBJECTIVE: To investigate the total surface bearing (TSB) prosthesis for below-knee amputee patients and to determine its clinical indications. DESIGN: Case series. SETTING: University hospital and the Welfare Center for the Disabled. PATIENTS: Thirty-two subjects who could walk with the TSB prosthesis and had already used the patellar-tendon bearing (or Kondylen-Bettung Münster) socket. MAIN OUTCOME MEASURE: Subjective assessment of the TSB socket, consisting of an overall rating and ratings of 13 individual items, was performed, and results were analyzed with Fisher's exact test. RESULTS: Seventy-five percent of the subjects were satisfied overall with the TSB socket. Of the 13 items, comfort, ease to swing, pain, piston movement, tightness, skin irritation, appearance, and durability were regarded as good by more than 75% of the patients. Donning, perspiration, odor, and staining were regarded as poor by more than 20%. Items that were significantly related with overall satisfaction with the TSB socket were comfort, ease to swing, and piston movement, while donning was significantly related to dissatisfaction. CONCLUSION: The TSB socket is suitable for and preferred by many amputee subjects, but some problems remain to be solved.
PURPOSE OF THE STUDY: The aim of the study is to assess the functional results and septic evolution in the treatment of infected total knee arthroplasties. MATERIAL AND METHODS: 22 patients were reviewed; 8 were initially treated in our institution and 14 transferred from other hospitals. Articular debridement alone leaving the prosthesis in situ was initiated in 3 of our 8 patients as well as in 6 of the transferred cases. In both groups, this procedure appeared to be a failure. Prosthetic-reimplantation procedure was elected in 10 patients either as a one-stage (5 cases) or a two-stage surgery (5 cases). This has been successfully rated in 7 cases. Femoro-tibial arthrodesis was performed in 15 patients, three of them being a failure of the prosthetic reimplantation. Follow-up ranges from 16 months to 9 years with well documented records. RESULTS: As stated earlier, articular debridement alone has not proven to be a helpful procedure since it did not eradicate the septic complication in any case. Prosthetic reimplantation has been a successful treatment in 7 of the 10 attempted cases. The one-stage procedure is providing the best functional result. Recurrent infection occurred in 3 cases: there were patients with poor host defense (diabetes, arteritis, old age, ...) with resistant bacteria complicating a hinge-knee prosthesis. Femoro-tibial arthrodesis was achieved in 10 of the 15 patients and necessitated all together 23 surgical operations. The highest union rate was observed in cases where sterile conditions were achieved, fixation being performed with an intramedullary nail. Failure of arthrodesis confines the patients in such an uncomfortable situation that 2 of them has asked for an amputation. DISCUSSION AND CONCLUSION: Early surgical debridement may occasionally salve a prosthesis when it is performed shortly after the onset of infection, in an unloosened unconstrained prosthesis infected by a low-virulence organism. In our study, no patient but one met those criteria. For those cases nevertheless, our procedure of choice is now the one-stage reimplantation who seems to be more effective for eradicating the infection and gives rise to a better clinical result. The two-stage reimplantation is the current procedure for handling an infected knee prosthesis. Some patients are still excluded from this procedure because of their poor health condition, bone loss, inadequate viability of skin and extensor mechanism or an uncontrolled sepsis. For such a case, arthrodesis remains the most reliable method of management, especially when it can be stabilized with an intramedullary fixation, which implies to perform a two-stage arthrodesis.
The in vivo rotary laxity and torsional stiffness of the knee joint were measured in 20 patients with wide intraarticular resection of the distal femoral tumor followed by reconstruction with a custom Kinematic rotating hinge endoprosthesis. The contralateral normal knee served as natural control. Twenty patients underwent 29 measurements, including 9 at the first year, 10 at the second year (4 of these also measured at year 1), and 10 at the third year (3 of these also measured at years 1 and 2; 2 also measured at year 2). The mean followup for the 15 survivors was 134 months (range, 102-156 months). The total rotatory laxity of the hinged knee was significantly greater than that of the contralateral knee. The torsional stiffness in external rotation of the hinged knee was 30.4% less than that of the contralateral knee in the first postoperative year, whereas the torsional stiffness in internal rotation was similar to that of the contralateral knee. Torsional stiffness of the hinged knee in the second year was significantly less than that of the contralateral knee whereas it was within the normal range of stiffness in the third year. The total rotatory laxity and torsional stiffness of the hinged knee in the early postoperative years could not predict the risk of late loosening. In vitro rotational stability of the rotating hinge device with axial load bearing was 6.7 and 8.1 Newton-meters (N-m) at 0 degrees and 20 degrees knee flexion, respectively, under an axial tibial load of 945 Newtons.