Two-Year Revision Rates in Total Ankle Replacement Versus Ankle Arthrodesis: A Population-Based Propensity-Score-Matched Comparison from New York State and California

Abstract

Background:The aim of this study was to compare outcomes between total ankle replacement (TAR) and ankle arthrodesis (AA) for ankle osteoarthritis using real-world data.Methods:We used longitudinal claims data from New York State from October 2015 to December 2018, and from California from October 2015 to December 2017. The primary outcome was revision. Secondary outcomes were in-hospital complications and below-the-knee amputation. Propensity-score matching adjusted for differences in baseline characteristics. To determine predictors of the main outcome, each group was analyzed using multivariable Cox regressions.Results:There were 1,477 TAR procedures (50.2%) and 1,468 AA procedures (49.8%). Patients undergoing TAR were less likely to belong to a minority group and had fewer comorbidities compared with those undergoing AA. Crude analyses indicated that the TAR group had a lower risk of revision (5.4% versus 9.1%), in-hospital complications (<1% versus 1.8%), and below-the-knee amputation (<1% versus 4.9%) (p < 0.001 for all). However, in the propensity-score-matched analysis, the risk of revision was no longer significantly lower (TAR, 5.6% versus AA, 7.6%; p = 0.16). In the multivariable analyses, older age was predictive of a lower risk of revision after TAR (hazard ratio [HR], 0.96 [95% confidence interval (CI), 0.93 to 1.00]), but age was not predictive of revision after AA (HR, 0.99 [95% CI, 0.97 to 1.01]). Female patients were less likely to undergo revision after AA (HR, 0.61 [95% CI, 0.39 to 0.96]), but sex was not predictive of revision after TAR (HR, 0.90 [95% CI, 0.51 to 1.60]).Conclusions:The 2-year adjusted revision risk was 5.6% after TAR and 7.6% after AA. This difference did not reach significance. Older age was a predictor of lower revision risk after TAR. Men had a higher risk of revision than women after AA. The number of TAR procedures has now caught up with the number of AA procedures.Level of Evidence:Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.