Midterm Outcomes Following Total Knee Arthroplasty in Lupus Patients

Background: An increasing number of patients with systemic lupus erythematosus (SLE) are undergoing total knee arthroplasty (TKA), but there are few studies detailing their outcomes. The purpose of this study was to evaluate TKA cohort of patients who had SLE compared with a matched cohort who did not have this disease by analyzing (1) implant survivorship, (2) functional outcomes, (3) complication rates, (4) health-related quality of life, and (5) patient-perceived activity level. Methods: A retrospective review of all patients who underwent TKA and had an International Classification of Diseases, Ninth Revision, code diagnosis for SLE was performed at 3 high-volume institutions. A total of 31 patients (34 arthroplasties) were identified, and they were compared with a matched cohort (1:3) who did not have SLE and had undergone a primary TKA during this same time period. Results: After a mean 6-year follow-up (range, 2-10 years), both cohorts had similar implant survivorship (91% vs 99%). In addition, each cohort had similar complication rates (odds ratio = 1.9, 0.99-13). Functional outcomes were similar as measured by Knee Society Scores objective (90 vs 91 points) and functional (89 vs 90 points). There were no differences in Short Form-36 physical (47 vs 49 points) or mental components (51 vs 53 points). University of California Los Angeles activity scores were similar as well (5.1 vs 5.9 points). Conclusions: Our study demonstrated comparable excellent clinical and patient-reported outcomes of TKA in patients with or without SLE. Prospective studies are necessary to evaluate these outcomes at longer follow-up.