To resurface or not to resurface: the patellar dilemma in total knee arthroplasty

Introduction
Total knee arthroplasty (TKA) is a highly successful clinical procedure, but there is no consensus regarding optimal patellar management. Options include patellar resurfacing and nonresurfacing, with the latter sometimes involving de-afferentation. Anterior knee pain post-TKA affects 5–20% of patients with patellar retention, prompting varied surgical approaches. Over 80% of surgeons prefer patellar resurfacing due to its cost-effectiveness, fewer re-operations, and reduced anterior knee pain. However, resurfacing has risks like patellar fracture, dislocation, implant failure, and patellar tendon damage. Proponents of patellar retention argue against its additional complexities and lack of clear benefits. Nonresurfacing correlates with higher anterior knee pain rates, necessitating more interventions and re-operations. Despite randomized trials, the superiority of either option remains unclear.
Patients and methods
Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we conducted a meta-analysis of comparative studies on patellar resurfacing versus nonresurfacing in TKA, focusing on revision and complication rates. A comprehensive search of MEDLINE, EMBASE, Cochrane, and PubMed databases was performed using keywords such as ‘Knee,’ ‘Arthroplasty,’ ‘Patella,’ ‘Resurfacing,’ ‘Prosthesis,’ and ‘Replacement.’ Two independent reviewers assessed articles for relevance and extracted data. Inclusion criteria included detailed surgical procedure descriptions, sufficient follow-up duration, and at least one validated outcome score. Studies lacking these parameters were excluded. The risk of bias was assessed using the ROBIS tool.
Results
Out of 1885 citations, 35 studies met the inclusion criteria, comprising 5304 TKAs (2345 nonresurfaced, 2359 resurfaced). The average follow-up duration was 58.1±37.1 months. The meta-analysis revealed a significantly lower re-operation rate in the resurfaced group (1%) compared with the nonresurfaced group (6.9%) [Odd’s ratio (OR) 0.18, 95% Confidence interval (CI) 0.11–0.29, P<0.00001]. Anterior knee pain was also significantly lower in the resurfaced group (2%) compared with the nonresurfaced group (10%) [OR 0.17, 95% CI 0.12–0.25, P<0.00001]. Additionally, the resurfaced group showed higher postoperative Knee Society Score pain scores (Mean difference 1.52, 95% CI 0.68–2.35, P=0.0004) and Hospital for Special Surgery scores (Mean difference 4.35, 95% CI 3.21–5.49, P<0.00001). The results were shown on a forest and funnel plot diagram.
Conclusion
Patellar resurfacing in TKA demonstrated superior outcomes compared with nonresurfacing, with lower re-operation rates, reduced anterior knee pain, and better Knee Society Score pain and Hospital for Special Surgery scores. These findings suggest the potential benefits of patellar resurfacing in TKA. However, standardized reporting of follow-up durations and outcomes in larger randomized controlled trials is essential to enhance understanding and guide clinical decisions on patellar management in TKA patients.