Reactivation of rheumatoid arthritis in knees following total knee replacement

Between May 1985 and December 1990, 20 patients with rheumatoid arthritis had 34 total knee replacements performed. The mean follow-up period was 4.1 years and the range was 2.3 to 7.8 years. Five knees with total knee replacements (74.7%) in 4 patients were affected by activation of the rheumatoid process at an average postoperative interval of 28.6 months while the other 29 knees with total knee replacements (85.3%) remained in remission. Factors that appeared to have an influence on post total knee replacement rheumatoid activation included the activity of the disease preoperatively, and whether synovectomy was undertaken at surgery. Whether patella replacement was undertaken appeared not to have influenced postoperative reactivation of the disease. Using the Hospital for Special Surgery Knee score, total knee replacement in our cases gave excellent results. The complications included one knee with dislocation of the patella and another with infection.