Knee kinematics of posterior cruciate ligament sacrificed total knee arthroplasty.

Abstract

Two different posterior stabilizing mechanisms in posterior cruciate ligament sacrificing total knee arthroplasty were evaluated to test knee kinematics, tibiofemoral contact location, and the quadriceps force needed to extend the knee. A posterior stabilizing post and a deeply dished polyethylene with a high anterior lip (anterior buildup stabilizing tibial articular surface) were tested in four anatomic specimen knees with a knee kinematics testing device. Both posterior stabilizing mechanisms partially restored anteroposterior stability, but the knees were still more lax than were the normal knees in the anteroposterior direction. The anterior buildup stabilizing tibial articular surface decreased rotational laxity in early flexion. Tibiofemoral contact location in the knees with the anterior buildup stabilizing tibial articular surface did not move posteriorly as the knee flexed, and the knees with this articular surface required significantly more quadriceps force to extend the knee than did the knees with a stabilizing post.