Simultaneous Total Ankle Replacement and Contralateral Ankle Arthrodesis for Bilateral Ankle Osteoarthritis: A Retrospective Study Focused on Clinical Outcomes and Cost-effectiveness.

OBJECTIVE: Total ankle replacement (TAR) and ankle arthrodesis (AA) are two common surgical treatment options for end-stage ankle osteoarthritis. However, few reports compare the outcomes of simultaneous TAR and contralateral AA for bilateral ankle osteoarthritis. The aim of this study was to assess changes in pain, joint range of movement (ROM), functional outcomes, patient satisfaction, and cost-effectiveness following simultaneous TAR and contralateral AA. METHODS: A retrospective study was conducted on 12 patients with bilateral end-stage ankle osteoarthritis who underwent simultaneous TAR and contralateral AA in our institution between May 2016 and August 2018, and who had a minimum of two-year follow-up data. Clinical and radiological follow-up data for all patients were collected after 4 months, 1 year and 2 years. The results were assessed clinically on a visual analogue scale (VAS) and included ROM, American Orthopedic Foot and Ankle Society (AOFAS) ankle hindfoot score, and satisfaction questionnaire. The total hospital costs of patients were also recorded. Independent sample t tests were conducted to compare continuous variables between groups. Paired sample t-tests were conducted to compare changes from the preoperative to postoperative evaluations within each group. RESULTS: Both surgical groups presented with pain reduction (P < 0.001) at the one-year postoperative session, which was generally consistent until the two-year follow-up. There was a significant increase (P < 0.001) in the mean AOFAS score postoperatively in both ankles. The functional outcomes at the one- and two-year follow-up were significantly better in patients in the TAR group than in those in the AA group (P < 0.001). Joint ROM differences were observed between the two groups after surgery (decreased ankle ROM in arthrodesis, P < 0.001; increased ankle ROM in arthroplasty, P < 0.001). The mean satisfaction score was 2 (range, 1-4) for the TAR group and 3 (range, 1-5) for the AA group. A significant difference in the satisfaction score was observed between the two groups (P = 0.036). Simultaneous TAR and contralateral AA was 34.1% less expensive than simultaneous bilateral TAR. No intraoperative complications were noted in either group. Wound healing occurred without problems within 2 weeks after surgery. No symptomatic deep venous thrombosis was found during follow-up. CONCLUSION: TAR had better patient-perceived post-operative function and preserves more anatomic sagittal plane motion compared to ankles undergoing AA. In addition, simultaneous TAR and contralateral AA are more cost-effective than simultaneous bilateral TAR, with lower costs for the average patient.