Fixed-Bearing Trabecular Metal Total Ankle Arthroplasty Using the Transfibular Approach for End-Stage Ankle Osteoarthritis: An International Non-Designer Multicenter Prospective Cohort Study

This multicenter prospective cohort study assessed the safety and performance of the Trabecular Metal Total Ankle System (TM Ankle; Zimmer) for primary total ankle arthroplasty (TAA). METHODS: One hundred and twenty-one consecutive patients qualifying for primary TAA were enrolled in the study. All patients received the TM Ankle implant. Clinical outcome examinations and radiographic evaluations were conducted at 6 weeks, 6 months, 1 year, 2 years, and 3 years. Patient-reported outcome measures (PROMs) were evaluated with use of the EuroQol-5 Dimensions questionnaire (EQ-5D), Ankle Osteoarthritis Scale (AOS), American Orthopaedic Foot & Ankle Society questionnaire (AOFAS), and patient satisfaction at each time point. Complications were classified according to the Canadian Orthopaedic Foot and Ankle Society (COFAS) system. RESULTS: The average AOFAS, EQ-5D, AOS pain, and AOS difficulty scores showed significant improvement at 6 weeks, 6 months, 1 year, 2 years, and 3 years as compared with the preoperative baseline (p < 0.001). The Kaplan-Meier survival estimate for revision when used in primary cases was 97.35% at 3 years. During the 3 years of follow-up, 9 patients showed abnormal radiographic findings. Two ankles had intraoperative complications, 38 had complications that were non-surgical or device-related, and 3 ankles underwent revision. CONCLUSIONS: The results of the present study indicated that patient well-being significantly increased following TAA with use of the TM Ankle. Radiographic parameters also demonstrated a low incidence of abnormal findings. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.