Full flexion after total knee replacement in rheumatoid arthritis.

The results of the Y-S total knee replacement are reported in 152 patients with rheumatoid arthritis (227 knees). The follow up was from 2 to 4 years (average 2.7 years). The good range of motion generally achieved was attributed to the use of a calibrated distractor for soft tissue balancing, a tibial prosthesis with a flattened plateau and extensive postoperative rehabilitation. Fourteen patients (27 knees) were able to squat fully after operation. A good range of motion before operation was related to a good range after operation. The range and overall results did not differ in patients with rheumatoid arthritis or osteoarthritis. The knees which recovered full flexion were no different from those with less than full flexion as far as stability and radiographic findings were concerned.