Comparison of patient reported outcomes using the Manchester-Oxford Foot Questionnaire and surgical complications following total ankle replacement in rheumatoid arthritis versus osteoarthritis

Total ankle replacement (TAR) is an alternative to ankle fusion for treatment of end stage ankle arthritis. It has been hypothesized that patients with rheumatoid arthritis may experience inferior outcomes due to altered immune response and low bone quality. Previous studies using the American Orthopaedic Foot & Ankle Society (AOFAS) score suggest patient reported outcomes following TAR for osteoarthritis (OA) versus rheumatoid arthritis (RA) are indifferent, however the AOFAS score has limitations and has largely been superseded by the Manchester-Oxford Foot Questionnaire (MOXFQ) score, which demonstrates favourable data characteristics. The aims of the present study were to compare outcomes in RA versus OA following TAR using the MOXFQ and describe associated complication rates. This single-center cohort study included 114 patients (143 TARs) who underwent primary TAR from 2010 to 2023. Data included patient demographics, comorbidities, satisfaction and MOXFQ. Multivariate logistic regression was used to assess differences in outcomes between OA versus RA adjusting for demographic covariates. Change in MOXFQ score following TAR was equal between the RA and OA group after adjusting for demographic co-variates (OR, 1.01 [95 % CI, 0.99-10.3], p = 0.284). RA was associated with increased risk of wound healing complications (OR 11.75 [95 %CI, 1.06-130.32], p = 0.045). RA status did not influence the likelihood of requiring a revision operation, though this finding lacked sufficient statistical power. RA status was not demonstrated to significantly affect change in MOXFQ score following TAR. Wound healing complications were higher in RA patients, while other surgical and medical complications rates were equivalent.