Total Ankle Arthroplasty (TAR) vs. Ankle Arthrodesis (AA) for Primary Ankle Osteoarthritis: A Nationwide Analysis

CATEGORY: Ankle Arthritis; Ankle INTRODUCTION/PURPOSE: Ankle arthrodesis (AA) has historically been the gold standard for operative management of end-stage ankle osteoarthritis (OA). Recent increases in utilization of total ankle arthroplasty (TAR) have been observed secondary to new implant designs, improved surgical technique, and favorable functional outcomes. However, there is minimal data comparing clinical complications between the two procedures. The purpose of this study was to compare incidences of postoperative joint and systemic complications for patients that received primary AA vs. TAR for primary ankle osteoarthritis between 2007-2017 using a comprehensive Medicare database. METHODS: A retrospective review of patients that received primary AA or TAR was performed using the PearlDiver database (Fort Wayne, IN). All patients and associated complications were identified using ICD-9/ICD-10 and CPT codes. Patients with a history of ankle fracture, prior AA/TAR, or active ankle infection during the index procedure were excluded. Demographic data and overall joint complication rates were compared at 90-days, 1-year, and 2-years postoperatively using a Chi-Square test. Postoperative rates of subtalar fusion, prosthetic joint infection, hardware removal, periprosthetic fracture, and systemic complications were compared using logistic regression. Statistical significance was set at p < 0.05. RESULTS: A total of 1,580 patients received operative management of primary ankle OA: 1,100 (70%) patients received AA and 480 (30%) patients received TAR. The overall joint complication rate was higher in the AA group at 90-days (30% vs. 17%, p < 0.001), 1-year (36% vs. 21%, p < 0.001), and 2-years (38% vs. 22%, p < 0.001) post-discharge. AA patients were more likely to have a subsequent subtalar fusion at 90-days (OR 4.49), 1-year (OR 5.10), and 2-years (OR 5.36) post-discharge, as well as periprosthetic fracture at 1-year (OR 1.69) and 2-years (OR 1.77). Hardware removal was less likely for AA patients at 90-days (OR 0.43), 1-year (OR 0.41), and 2-years (OR 0.43). Neither group was more likely to develop systemic complications postoperatively. CONCLUSION: The present study found that AA patients have higher incidences of major joint complications in both the short- term and mid-term. Patients that received AA were more likely to have a subsequent subtalar fusion and sustain a periprosthetic fracture. Relative to TAR patients, a greater proportion of these patients were under the age of 65, obese, had diabetes, and used tobacco. TAR patients were more likely to have hardware removal post-discharge. Further study is warranted to better quantify patient selection for AA vs. TAR and trend the long-term complications of these procedures.