Simultaneous bilateral total knee arthroplasty with and without patellar resurfacing using a zirconium ceramic femoral component demonstrated equivalent short-term outcomes: A prospective randomised clinical trial.

PURPOSE: The optimal management of the patella during total knee arthroplasty (TKA) has not been updated with the development of prosthesis. The purpose of this prospective randomised clinical trial was to compare the physical findings and patient-reported outcome measures between knees with patellar resurfacing and those without patellar resurfacing in the same patients undergoing simultaneous bilateral TKA using a contemporary zirconium ceramic femoral component.

METHODS

Forty patients (80 knees) scheduled for simultaneous bilateral primary TKA due to osteoarthritis received patellar resurfacing on one side knee indicated by randomisation (either left or right) and patellar non-resurfacing on the opposite side. A posterior-stabilised prosthesis with the contemporary zirconium ceramic patella-friendly femoral component (ACTIYAS Kyocera, Kyoto, Japan) was used with the measured resection technique with mechanical alignment in all cases. All patients were followed for a minimum of 2 years. Knee Society knee score and function score, the 2011 Knee Society score, numerical rating scale for pain, patient overall assessment of the knee (0 being "worst"-100 being "normal"), and symptom around the patella were compared between the two groups.

RESULTS

There were no significant differences in postoperative objective knee indicators, postoperative patient-reported outcome measures, and postoperative examination of the patellofemoral joint between the knees that received patellar resurfacing and patellar non-resurfacing, without baseline differences. Patient overall assessment of the knee averaged 86.3 in the patella resurfacing group while 84.2 in the non-resurfacing group (p = 0.142). Objective knee indicators and the patient-reported outcome measures increased significantly after surgery in both groups. Secondary resurfacing and reoperation were not required for any patellar resurfacing or non-resurfacing knees.

CONCLUSION

Excellent physical findings and patient-reported outcome measures were observed following TKA with the contemporary zirconium ceramic femoral component, regardless of whether patellar resurfacing was performed, in the short term.

LEVEL OF EVIDENCE: Level II, lower quality randomised trials.