Patellar Resurfacing in Total Knee ArthroplastyA Meta-Analysis

BACKGROUND: Patellar resurfacing during total knee arthroplasty remains controversial. We aimed to evaluate the effectiveness of this technique through an evaluation of the current literature. METHODS: We performed a meta-analysis of randomized controlled trials comparing total knee arthroplasties performed with and without patellar resurfacing. Outcomes of interest included the number of reoperations, the prevalence of postoperative anterior knee pain, and the improvement in various knee scores. RESULTS: Ten trials assessing 1223 knees were eligible. The absolute risk of reoperation was reduced by 4.6% (95% confidence interval, 1.9% to 7.3%) in the patellar resurfacing arm (between-study heterogeneity, p < 0.01; I(2) = 60%), implying that one would have to resurface twenty-two patellae (95% confidence interval, fourteen to fifty-two patellae) in order to prevent one reoperation. Patellar resurfacing reduced the absolute risk of postoperative anterior knee pain by 13.8% (95% confidence interval, 6.4% to 21.2%), implying that one would have to resurface seven patellae (95% confidence interval, five to sixteen patellae) in order to prevent one case of postoperative anterior knee pain. Only four trials provided adequate data for a quantitative synthesis of the changes in the various knee scores; on the basis of those four trials, there was no difference in the mean improvement in the knee scores (standardized mean difference, 0.03; 95% confidence interval, -0.50 to 0.56). CONCLUSIONS: The available evidence indicates that patellar resurfacing reduces the risks of reoperation and anterior knee pain after total knee arthroplasty. The observed effects are clinically important despite their modest magnitude. Additional, carefully designed randomized trials are required to strengthen this claim.