Was Mark Reiley Right? A Outcome Analysis of Intramedullary Versus Extramedullaryalignment Referencing for Total Ankle Replacement

Abstract

Category: Ankle Arthritis; Ankle Introduction/Purpose: The purpose of this study was to report on the radiographic outcomes, clinical outcomes, and implant survivorship following extramedullary-referenced (EMr) versus intramedullary-referenced (IMr) total ankle replacement (TAR). Methods: From May 2007 to February 2018, a consecutive series of patients with end-stage tibiotalar osteoarthritis undergoing TAR for primary arthritis, post-traumatic arthritis, and inflammatory arthritis was enrolled in this study. Analyses were performed comparing IMr versus EMr components for patient-reported outcomes data, pre and postoperative radiographic ankle alignment, concomitant procedures, and complications. Kaplan-Meier survivorship analyses served to determine implant reoperation and revision surgery. Data was prospectively collected and retrospectively analyzed. A p-value of 0.05). The 5-year implant survivorship was 98.6.% for IMr versus 97.5% for EMr at final follow-up. Conclusion: Despite the IMr TAR group having more severe preoperative coronal and sagittal malalignment, both IMr and EMr TAR components had comparable postoperative alignment, patient-reported outcome scores, and complications. Among the patients with preoperative varus, valgus, or anterior distal tibial slope, the IMr patients achieved greater correction than the EMr patients. Although the 5-year implant survivorship was similar between the two cohorts with 98.6% survival for IMr TAR and 97.5% for EMr TAR, impending failures were greater for the mobile-bearing EMr TAR.