Unicompartmental knee arthroplasty in patients with Parkinson’s disease

INTRODUCTION: Patients with Parkinson's disease (PD) are a vulnerable subgroup facing elevated risks of complications and functional decline following knee arthroplasty. However, data on the outcomes of minimally invasive unicompartmental knee arthroplasty (UKA) in this population are limited. This study´s purpose was to assess perioperative complications, implant revision-free and reoperation-free survivorship as well as functional outcome in PD patients following UKA. MATERIALS AND METHODS: In this retrospective single-center study, 42 knees in 39 patients with PD who underwent medial or lateral UKA between 2016 and 2022 were analyzed. The mean age was 70.6 ± 9.1 years, and the mean BMI was 27.9 ± 5.2 kg/m². A total of 26 medial and 16 lateral UKAs were performed, with a minimum follow-up of two years (mean 5.0 ± 2.0). All medical complications were recorded. Implant survivorship (tibia and/or femur) and reoperation-free survival were evaluated using Kaplan-Meier analysis, allowing estimation of long-term survival beyond the mean follow-up duration. Functional outcomes were assessed using the Oxford Knee Score (OKS) and the UCLA Activity Score. RESULTS: Of the 42 knees, 6 (14.3%) underwent reoperation, including 4 cases (9.5%) requiring implant revision. The cumulative 9-year implant survivorship was 90.5% (95% CI: 81.7-99.3), and reoperation-free survival was 85.7% (95% CI: 75.1-96.3), respectively. No perioperative cardiovascular complications occurred. OKS improved significantly from 16.2 ± 5.5 to 39.6 ± 7.1 (p = 0.027), while the UCLA Activity Score showed a trend towards improvement from 4.0 ± 2.0 to 5.0 ± 1.7 (p = 0.078). CONCLUSION: In this observational study, UKA in patients with PD was associated with favorable implant survivorship and encouraging functional outcomes. Considering the very low medical complication rate observed in this study, UKA may represent a viable treatment option for isolated end-stage unicompartmental osteoarthritis in carefully selected patients.