50 patients were randomized to determine the effect of synovectomy combined with total knee arthroplasty (TKA) in the treatment of patients with bilateral knee osteoarthritis presenting with bilateral synovial pathology. The knees of patients were allocated to TKA either with or without synovectomy, and were followed-up for one year. The results indicated that pain and function did not significantly differ between groups, and that blood loss was significantly greater in knees which were operated on with adjunct synovectomy. The findings did not support the routine use of combined synovectomy-TKA.