Survival of lateral unicompartmental knee arthroplasty at short‐, mid‐, and long‐term follow‐up: a systematic review and meta‐analysis

Abstract Background The infrequency of lateral unicompartmental knee arthroplasty (UKA) has led to a lack of understanding of its survival. This study aimed to systematically evaluate the survivorship results of lateral UKA at different follow‐ups based on available literature. Methods Five databases were searched for eligible studies. Pooled survivorships with 95% confidence intervals (CIs) at 3, 5, 10, 15, and 20 years after lateral UKA were estimated using a random‐effect model. Subgroup and sensitivity analyses were performed. Results A total of 26 studies involving 5470 lateral UKAs were included. Survivorships of lateral UKA at 3‐, 5‐, 10‐, 15‐, and 20‐year follow‐ups were 96% (95% CI: 95–98%, I 2 : 77.5%), 94% (95% CI: 93–96%, I 2 : 70.8%), 88% (95% CI: 84–91%, I 2 : 70.8%), 85% (95% CI: 79–91%, I 2 : 70.8%), and 78% (95% CI: 71–85%, I 2 : 54.2%), respectively. Subgroup analyses found that bearing type, the number of surgeons, and year of publication might be associated with implant survival outcomes. Conclusion Lateral UKA is an effective procedure with excellent survivorships at short‐, mid‐, and long‐term follow‐ups. Results suggest a single‐surgeon lateral UKA using fixed‐bearing. Additional well‐designed studies are needed to elucidate the current findings.