Management of the patella during total knee arthroplasty (TKA) remains controversial. Some surgeons argue that (almost) all TKA patients should undergo primary patella resurfacing, because of the higher revision rate among patients without primary patella resurfacing reported in registry studies. Other surgeons argue against resurfacing, claiming this higher revision rate is due to pain and subject to a revision bias, because a patella-specific revision is significantly easier when the patella was not resurfaced. One important question is whether TKA patients without primary patella resurfacing report more pain. We aimed to assess revision risk and early postoperative patient-reported outcome measures in our centre between patients with and without primary patella resurfacing. Our cohort included all TKA patients from our centre between January 1, 2005 and July 15, 2024, who had a primary TKA with one of three high-volume knee systems with a known constraint, patient gender, and BMI. All surgeries were performed by fellowship-trained arthroplasty surgeons. We used Oxford Knee Score (OKS) and satisfaction data collected preoperatively and at one and two years postoperatively. We derived patella pain and patella function subscores from specific questions in the OKS questionnaire. We further identified subsequent revisions on the same knee from our database. We used logistic regression to estimate the association between primary patella resurfacing and postoperative pain and function and used Cox proportional hazard models to estimate the association with revision TKA while adjusting for various confounding factors. We identified 10,846 TKA patients of which around 78% had their patella resurfaced during their primary TKA. Most patients (96%) with primary patella resurfacing received a posterior stabilized knee, compared to roughly half without primary patella resurfacing. Preoperative OKS was the same for both groups. At 1 year, 54% of patients with resurfacing experienced pain vs 52% for patients without resurfacing (adjusted odds ratio OR 0.9; 95% confidence interval CI 0.8–1.1) and 78% vs 77% of all patients experienced functional patella issues (OR 1.0; 95% CI 0.8–1.2). Patients with patella resurfacing were slightly more satisfied at 2 years (80%) than those without (76%); OR = 1.4 (95% CI 1.0–1.9). Patients with patella resurfacing were slightly less like to be revised, e.g., the adjusted hazard ratio with follow-up to 2 years was 0.6 (95% CI 0.4–1.0). Overall, postoperative pain and function is similar between TKA patients with and without primary patella resurfacing. We found a slightly higher revision rate in patients without primary patella resurfacing, in line with what registries report. Although patients without primary patella resurfacing generally fare well, it is possible that a small subset of patients experiences worse outcomes that lead to revision; more work is needed to understand why.
Righolt et al. (Wed,) studied this question.