Patella resurfacing: no benefit for the long-term outcome of total knee arthroplasty. A 10- to 16.3-year follow-up.

A follow-up of more than 10 years among patients who have undergone a total knee arthroplasty (TKA) was performed to determine the significance of patella resurfacing for the long-term outcome. The clinical outcome was assessed by the Knee Society Score (KSS), and the radiological outcome was determined based on the Knee Society Roentgenographic Evaluation System. The patella was preserved in 21 knees and resurfaced in 44 knees. The mean follow-up time was 11.6 years (range 10-16.3 years). There was no significant difference in the clinical outcome between the knees with patella resurfacing (knee points: mean 85.3 +/-12.9, function points: mean 70.3 +/- 23.4) and the knees with patella retention (knee points: mean 82.7 +/- 16.2, function points: mean 71.7 +/- 22.4; p = 0.58 for knee, and p = 0.83 for function points). There was also no significant difference in the radiological outcomes regarding the angles alpha, beta, Upsilon, delta, and valgus ( p > 0.05 for each variable). There was, however, a trend towards more lucencies in TKAs with a resurfaced patella on the tibia side in the anteroposterior view ( p = 0.052). Patellar complications were found more often in the resurfaced group (20.5%) than in the group without resurfacing (9.6%). The results indicate overall no advantage of patella resurfacing compared with patella retention in the long run.