In vitro study of knee stability after two-band two-tunnel posterior cruciate ligament reconstruction

摘要

＜正＞Objective: To compare the ability of three different reconstruction procedures in restoring the posterior displacement of tibia and the posterior stability of the knee joint from 0°to 120°flexion. Methods: Three posterior cruciate ligaments （PCL） reconstruction procedures were performed, namely two-band two-tunnel reconstruction, one-band anterior tunnel reconstruction and one-band posterior tunnel reconstruction. The posterior displacement of the tibia in relation to the femur was measured when a 200 N posterior force was applied. Results: Within the flexion range of 0°to 30°, the displacement in the one-band posterior tunnel reconstruction showed little difference from that of an intact knee （P＞0.05）. But when the flexion exceeded 30°, especially when it exceeded 60°, the displacement in one band posterior tunnel reconstruction was much greater than that of an intact knee （P＜0.01）. In two-band two-tunnel reconstruction and one-band anterior tunnel reconstruction, the displacement was approximately the same as that of an intact knee ranging from 0°to 120°（P＞0.05）, while a slight over-restriction might be found at some angles. Conclusions: Two-band reconstruction could effectively restrict the posterior displacement of the tibia and restore anterior, posterior stability of the knee joint within its full range of flexion. One-band anterior tunnel reconstruction also could maintain the posterior stability of the knee, while the result of one-band posterior tunnel reconstruction is the most unsatisfactory.