Outcome of mobile and fixed unicompartmental knee arthroplasty and risk factors for revision

OBJECTIVES: In this study, we aimed to evaluate the outcomes of patients undergoing unilateral knee arthroplasty (UKA) and to analyze risk factors that may lead to revision in patients who undergo UKA. METHODS: We included patients who underwent mobile or fixed UKA owing to osteoarthritis and who had at least 24 months of follow-up in the postoperative period. We recorded information on patient age, sex, side, body mass (kg/m(2)), follow-up duration, Knee Society Score, Western Ontario and McMaster Universities Arthritis Index (WOMAC) pain, WOMAC function, WOMAC stiffness, mechanical axle angle, femoral component compliance, tibial component compliance, accumulated experience of the surgeon, and revision status. RESULTS: In total, we evaluated 131 knees in 118 patients. 50 (38%) who underwent mobile UKA and 81 (62%) who underwent fixed UKA. The effect of obesity on mobile and fixed UKA revision was significant. The likelihood of revision decreased with greater experience of the surgeon performing UKA. CONCLUSION: Our study showed that the clinical results of mobile and fixed UKA procedures are similar. We also revealed that obesity poses a risk for revision in both fixed and mobile UKA, and the revision rate decreases with increased experience of the surgeon.