Preliminary report on postoperative results of newly designed stable total knee prosthesis

Long-term results of Yoshino total knee arthroplasties in rheumatoid arthritis

A review was made of 267 Yoshino total knee arthroplasties performed on 184 patients with rheumatoid arthritis between June 1978 and December 1983. The average duration of follow-up was 14.3 years. Of these patients 46.7% died during the follow-up period. The main causes of death were cardiac disease, respiratory disease and renal disease. According to the Japanese Orthopaedic Association (JOA) knee rating system, JOA scores decreased significantly with time after surgery, but remained significantly higher than the preoperative scores. The flexion angle after surgery had decreased compared with the preoperative flexion angle and decreased further 3 years after surgery and later. The cumulative survival rate was 88.6%. This rate was mainly affected by postoperative infection and aseptic loosening of the tibial components.

Total knee arthroplasty in Charcot's joint

The authors report three cases with neuropathic (Charcot) knee joint due to tabes dorsalis in which total knee arthroplasty (TKA) was performed. Three cases (5 joints) were observed for more than 8 years after TKA. No ataxia was seen before or after surgery. The postoperative clinical course had been satisfactory in two cases (3 joints) for 9-10 years after TKA with no evidence of loosening. Although the other case had medial condylar fracture of the right upper tibia during postoperative treatment, the clinical course of the right knee had been satisfactory over the 7 years since revision arthroplasty using a tibial component with a long stem. This case also had loosening of the left tibial component 8 years after TKA. Total knee arthroplasty appears to be useful for the treatment of Charcot's joint with no ataxia at Eichenholtz' stage of coalescence and reconstruction if (1) proper surgical techniques to establish good ligamentous balancing and bony alignment by releasing ligaments are employed; (2) an adequate amount of bone is resected and remaining bony defects are reinforced with bone graft; (3) long-stem components are used on both the femoral and tibial sides.

Postoperative results of Yoshino total knee prosthesis. A report of 264 arthroplasties performed between 1974 and 1980

A review was made of 264 Yoshino total knee arthroplasties performed on 154 patients between February 1974 and July 1980. The average duration of the follow-up was 3 years and 2 months. Eighty-six percent were rheumatoid patients. Complications occurred in seven patients. The evaluation results indicated excellent relief of pain and improvement in walking ability. However, pain of the patellofemoral joint was noted in a number of osteoarthritic patients. This implies that a patella implant is necessary in the case of osteoarthritis. In addition, a new surgical technique was performed on "stiff" knees to improve their degree of movement; the average range of movement achieved in these patients was 70 degrees.