15-Year Follow-Up of Mobile Bearing Medial Unicompartmental Knee Arthroplasty

Introduction: Medial unicompartmental knee arthroplasty (UKA) is a successful treatment for antero-medial osteoarthritis. However, there are few published studies on the long-term survival of this pro-cedure. The purpose of this study was to review the 15-year minimum outcomes and survival of a mobile-bearing medial UKA. Methods: A retrospective review was performed between July 2004 and December 2006 of all patients who underwent a medial UKA eligible for a minimum of 15-year follow-up. The initial query revealed 299 patients (349 knees). One hundred-seventeen patients died or were lost to follow-up, leaving 182 patients (219 knees) for analyses. Clinical outcomes and survivorship were analyzed. Results: There were 59 implant-related reoperations which occurred at a mean of 10 years (range, 0 to 16 years). The most common reasons for reoperation were arthritic progression (9.1%) and aseptic loosening (9.1%). The 10-year survival with revision to TKA was 89% (95% confidence interval: 86% to 92.4%), and the 15-year survival was 84.1% (95% confidence interval: 80.3% to 88%). There were no statistically significant differences in survival between sex, body mass index, and age. Patients who were not revised had sta-tistically significant improvements in knee range of motion and Knee Society scores. Conclusions: This study found similar long-term survival of a medial mobile-bearing UKA to published total knee arthroplasty outcomes. The implant evaluated in this study has undergone subsequent im-provements in instrumentation and design. Further analyses should be performed on the long-term outcomes of the current implant platform.& COPY; 2023 Elsevier Inc. All rights reserved.