Correcting lateral patellar tilt at the time of total knee arthroplasty can result in overuse of lateral release.

Abstract

Ninety-nine patients undergoing primary total knee arthroplasty were prospectively evaluated for pre-resurfacing and post-resurfacing patellar thickness and medial patellar liftoff at 30 degrees of flexion without manual pressure on the patella. Regardless of medial patellar liftoff, no lateral releases were performed. Tibiofemoral angles, patellar tilt, and patellar congruence angles were measured preoperatively and postoperatively. There were no patellar subluxations, dislocations, or complications related to the patellofemoral joint. Patellar tilt improved from 7.9 degrees preoperatively to 3.8 degrees postoperatively. Patients with 10 mm or more of intraoperative liftoff improved from 9.9 degrees tilt preoperatively to 6.6 degrees postoperatively. Patients with no intraoperative liftoff had a change from 6.3 degrees to 2.9 degrees . Although the 2 groups were statistically different, the amount of change in alignment was not different between the groups. Patients with medial patellar liftoff at the time of arthroplasty do not appear to require lateral release to yield acceptable postoperative patellofemoral alignment.