Patellar Resurfacing as a Prognostic Factor in Total Knee Arthroplasty: 20-Year Cohort Study

Abstract. Background: The decision to perform patellar resurfacing (PR) during total knee arthroplasty (TKA) is based on patient and implant characteristics. This study aims to evaluate PR as a prognostic factor for revision in primary TKA with 20 years of follow-up experience. Methods: This is a retrospective, comparative, observational cohort study of patients who underwent TKA at a high-specialty hospital in Mexico between 2000 and 2020. A total of 334 patients who underwent TKA were evaluated. For our TKA population we divided in two groups of interest: those with patellar PR and without patellar resurfacing (WPR). We analyzed various metrics for these patients, including complications, functionality, survival rates, and statistical associations. Functionality was evaluated using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Oxford Knee Score (OKS) scales. Pain was evaluated using the numeric rating scale (NRS). We determined the survival of TKA using the Kaplan-Meier method, and to evaluate prognostic variables, we used measures of association, such as the odds ratio (OR) and risk ratio (RR), along with the hazard ratio test (HR), with a 95% confidence interval (IC). A p-value of less than 0.05 was considered statistically significant. Results: TKA with PR was associated with improved clinical and functional outcomes. There were fewer reported complications and fewer cases of prosthetic failure or revision surgery in patients receiving PR. Conclusion PR offers a clinically significant reduction in anterior knee pain and lowers the risk of aseptic loosening in TKA over a 20-year follow-up period. These findings advocate for a selective approach to resurfacing. It is recommended that PR be considered primarily to minimize complications. Bioethics Committee Approval: This study was conducted in accordance with the ethical standards of the Declaration of Helsinki and with approval from the research ethics committee and the research committee of the Instituto Nacional Ciencias Médicas Nutricion Salvador Zubiran in Mexico (REG. CONBIOETICA-09-CEI-011-20160627, OFICIO NO. MCONTROL-2459/2024). Keywords: arthroplasty, knee resurfacing, anterior knee pain, aseptic loosening, prognostic factor.