Short- to mid-term results of minimally invasive lateral unicompartmental knee replacement: 133 cases in a non-designer series

Introduction The aim of the current study was to demonstrate short- to mid-term survivorship as well as clinical outcome of lateral unicompartmental knee replacement (UKR) with a fixed-bearing (FB) design from a non-designer center using the Oxford Fixed Lateral prosthesis. Materials and methods This single-center retrospective cohort study reports the results of 133 consecutive lateral FB-UKR. Survivorship analysis was performed with different endpoints and clinical outcome was measured using the Oxford-Knee-Score (OKS), American-Knee-Society-Score (AKSS-O), range-of-motion (ROM) and visual-analog-scale for pain (VAS). Results There were two revision surgeries with conversion to total knee replacements (TKR) due to persistent pain resulting in a survival rate of 98.5% (95% CI 93.5–99.6) with a mean follow-up (FU) of 3.3 ± 1.8 years (range 1–8.5). All outcome scores, VAS and ROM showed a significant improvement at final FU ( p