Synovectomy of the knee results in a satisfactory degree of pain relief in rheumatoid arthritis. 52 synovectomies were performed in 40 patients. The mean length of follow-up was 7.8 years. We found satisfactory results in 88.4% of the cases and unsatisfactory results in 11.6%. We could see that this procedure is indicated in those cases that have a well preserved articular architecture, while if this is destroyed the result is poorer.