Comparison of Unicompartmental Knee Arthroplasty Versus High Tibial Osteotomy for Medial Knee Osteoarthritis: An Updated Meta-Analysis of 56,000 Patients.

Osteoarthritis (OA) is a prevalent degenerative joint disease primarily affecting hip and knee joints, with an estimated 300 million cases globally. This study is crucial as it provides an updated, comprehensive comparison of unicompartmental knee arthroplasty (UKA) and high tibial osteotomy (HTO) for treating medial knee osteoarthritis, offering valuable insights into their relative effectiveness. The findings aim to inform clinical decision-making and improve patient outcomes by identifying the superior treatment option. A comprehensive search was conducted across PubMed, Cochrane Library, and Google Scholar until August 1, 2024. Statistical analysis used Review Manager 5.4 with a random-effects model, risk ratio (RR), and mean differences (MD) with 95% confidence intervals (CI) for the dichotomous and continuous outcomes, respectively. The Newcastle-Ottawa Scale was used for quality assessment, and funnel plots were used to analyze publication bias. GRADE assessment was done to gauge the certainty of the evidence. Thirty-nine studies, involving a total of 56,686 patients, were evaluated for comparison. UKA significantly reduced the complications (RR = 0.37; 95% CI: [0.25, 0.54]; p < 0.0001; I = 30%), revision rates to total knee arthroplasty (TKA) (RR = 0.64; 95% CI: [0.41, 0.99]; p = 0.05; I = 72%) and postoperative pain (MD = -0.33; 95% CI: [-0.64, -0.03]; p = 0.03; I = 89%) compared to HTO, while range of motion (ROM) (RR = -3.55; 95% CI: [-7.16, 0.52]; p = 0.09; I = 98%) and walking speed (MD = 0.02; 95% CI: [-0.04, 0.07]; p = 0.56; I = 0%) and surgical site infections(RR = 1.40; 95% CI: [0.30, 6.53]; p = 0.67; I = 86%) were comparable. All the functional knee scores are comparable except the Hospital for Special Surgery (HSS) score, which is increased in UKA (MD = 2.63; 95% CI: [0.52, 4.74]; p = 0.01; I = 76%). UKA is superior to HTO, offering lower revision rates, reduced postoperative pain, fewer complications, and better functional scores.