A Prospective, Single-Center, Randomized Controlled Study Comparing Non-Resurfacing versus Resurfacing in a Cohort of 250 Posterior-Stabilized Total Knee Arthroplasty with a Minimum Five-Year Follow-Up.

Abstract

Despite extensive research, patellar management during total knee arthroplasty (TKA) remains controversial. We therefore asked: Is there a difference in clinical and radiological outcomes at a minimum five-year follow-up with a modern posterior-stabilized TKA performed with or without patellar resurfacing? This single-center prospective randomized trial included 250 knees (245 patients) undergoing primary TKA between April 2017 and November 2018. Exclusion criteria were isolated patello-femoral osteoarthritis, constrained TKA, and preoperative flexion less than 90°. Patients were randomized into patellar resurfacing (PR) or patellar non-resurfacing (PNR) groups, receiving the same posterior-stabilized "patella-friendly" prosthesis. Clinical evaluation at five-year follow-up included the Knee Society Score (KSS), Forgotten Joint Score (FJS), Kujala and Lille scores for anterior knee pain, and range of motion. Radiographic assessment evaluated patello-femoral osteoarthritis progression and patellar implant loosening. Complications and surgical revisions were recorded. There were 213 knees (109 in PR, 104 in PNR) available with a five-year follow-up (9% lost to follow-up and 4% deceased). Clinical outcomes showed no significant differences between groups (KSS-knee: P = 0.10; KSS-function: P = 0.19; FJS: P = 0.24; Kujala: P = 0.36; Lille: P = 0.43). There were five patients (4.5%) in PNR who required secondary patellar resurfacing, whereas two patients (1.8%) in PR required revision of the patellar button. The revision rate for patello-femoral causes was 3.8%, without significant difference between groups (P = 0.16). At 60 months, implant survival was similar between PR and PNR (93.6 and 91.8%; P = 0.96). This large prospective randomized study found no clinical advantage of routine patellar resurfacing at five-year follow-up. While resurfacing may reduce anterior knee pain, it also introduces risks such as fracture and maltracking. In the context of patella-friendly posterior-stabilized implants, these findings support a more selective approach, which should be guided by objective criteria.