Mobile - bearing knee arthroplasty: clinical results

ABSTRACT

Twenty three primary cemented mobile-bearing total knee arthroplasties were implanted in nineteen patients. All implants were of a posterior cruciate-retaining design and allow translation of the polyethylene in the anteroposterior plane and its rotation about the longitudinal axis of the limb. Fifteen patients [17 knees] had osteoarthritis and four patients [6 knees] had rheumatoid arthritis. The average follow-up was 30 months. Preoperatively, the average flexion contracture was 11.5° [range, 0°-25°] and the range of motion 100° [range, 50°-130°] At final follow-up, no knee had a flexion contracture. The average postoperative range of motion was 120° [range, 80°-140°]. Preoperatively the average knee score was 38 points, the average function score was 42 points and the average pain score was 16 points according to the scoring system of the Knee Society. At the time of most recent follow-up, the average knee score was 90 points, the average function score was 82 points and the average pain score was 43 points. Nineteen knees [82.6%] in this study had no evidence of radiolucent lines around any component. Superficial infection was detected in one knee. Patellar dislocation occurred in two knees [3-4 weeks postoperatively] which needed lateral retinacular release