Intra-articular reconstruction of the anterior cruciate ligament. An experimental study of length changes in different ligament reconstructions.

An anatomic model was developed to test different types of intra-articular anterior cruciate ligament reconstructions. Four cadaver knees were tested in an identical fashion. In each knee 12 different positions were tested. The results indicate that over-the-top repair is not suitable for anterior cruciate ligament reconstruction from a mechanical standpoint. It is likely that this type of repair in human knees will lead to excessive stretching and insufficiency of the reconstructed tissue. A posterior approach through the lateral femoral condyle is more desirable. The position of the tibial tunnel is less crucial, but a more anterior tunnel is preferable. When the tunnels are properly drilled, fixation of the reconstructed ligament is advocated with the knee in 45 degrees-90 degrees of flexion. Postoperative immobilization in 45 degrees of flexion is suggested.