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° 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° preoperatively to 3.8° postoperatively. Patients with 10 mm or more of intraoperative liftoff improved from 9.9° tilt preoperatively to 6.6° postoperatively. Patients with no intraoperative liftoff had a change from 6.3° to 2.9°. 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.
- lateral release
- patellar tilt
- primary total knee arthroplasty
- rule of no thumb
ASJC Scopus subject areas
- Orthopedics and Sports Medicine