Changes in anteroposterior stability following total knee arthroplasty.

This study evaluated the changes in anteroposterior stability at flexion and extension following posterior cruciate ligament (PCL)-retaining and PCL-substituting total knee arthroplasty (TKA), in comparison with normal knees. Altogether, 29 knees of 24 patients underwent either PCL-retaining ( n = 19) or PCL-substituting ( n = 10) TKA. Anteroposterior displacement was measured with a KT-2000 arthrometer preoperatively, 1 month after surgery, and again an average of 3 years after surgery. Anteroposterior stability at flexion and extension did not change following PCL-retaining TKA and was not significantly different from that of normal subjects, whereas anteroposterior stability increased following PCL-substituting TKA and was significantly greater than that of normal subjects an average of 3 years after surgery.