Fixed versus mobile bearing medial unicompartmental knee arthroplasty with the same femoral implant design: a randomised controlled trial with a minimum of 10-year follow-up.

Study Summary

163 patients with advanced medial compartment knee osteoarthritis were randomized to receive mobile-bearing medial unicompartmental knee arthroplasty or fixed-bearing medial unicompartmental knee arthroplasty, using the same Uniglide femoral component design. The primary outcome of interest was the Oxford Knee Score (OKS). Secondary outcomes of interest included the American Knee Society Score (AKSS), Western Ontario and McMaster University Osteoarthritis Index (WOMAC), implant survivorship, and complications/reoperations. Outcomes were assessed preoperatively and at 8 months, 2 years, 5 years, and 10 years after surgery. Overall, the results of the study revealed no statistically significant differences in patient-reported outcomes between fixed and mobile-bearing groups at long-term follow-up. However, revision within ten years was lower in the fixed-bearing group. These findings suggest that both bearing designs provide similar long-term clinical function, although mobile-bearing implants may carry a higher early revision risk.