Between 1970 and 1979, 123 synovectomies of the ankle joint were performed on 99 patients. Sixty two of these patients (81 ankles) were followed up for an average period of four years. Using Steinbrocker's classification 10 ankles had Stage I disease, 34 had Stage II, 33 had Stage III and 4 had Stage IV. In more than 80% of the joints pain and swelling significantly decreased after operation, with improvement in the range of motion and of the gait pattern. However the procedure did not change the walking distance or dependency upon walking aids, probably because the ankle joint was rarely the only joint of the lower extremity affected by rheumatoid arthritis.