Tunnel placement and knee kinematics after standard versus computer-assisted ACL reconstruction

摘要

Introduction: A number of recent studies have examined the use of image-guided (IG) computer systems for more effective tunnel placement during ACL reconstruction. Results suggest that IG systems allow more predictable and more accurate tunnel position [2-4]. Such studies have only assessed the anatomic position of computer-assisted tunnels, however, and have not investigated effects on knee kinematics. This study evaluated anterior translation and transverse rotation in the normal, ACL-deficient, and ACL-reconstructed knee. Tunnel placement and knee kinematics after ACL reconstruction were compared using an IG technique versus a standard transtibial technique. Methods: In 8 pairs of cadaver knees, one knee was randomly assigned to a transtibial reconstruction and the other to an IG (BrainLab, Vector Vision) reconstruction technique [1]. A bone-patellar tendon-bone autograft was harvested from each knee (all bone plugs were 25mm long), and sized for 10mm tunnels. Knees were dissected free of all skin, subcutaneous tissue, muscle and tendon, and the extensor mechanism was released proximally. The ACL, PCL, PLC, knee capsule, and collateral ligaments were left intact. The IG system measured anterior translation and transverse rotation in the all the knees before ACL harvest, after harvest, and after reconstruction. Transtibial tunnels were placed with a tibial guide that centered the tibial tunnel 7mm anterior to the PCL and a femoral guide that centered the femoral tunnel 7mm anterior to the posterior notch.