The Biomechanical Analysis of a Double Bundle Posterior Cruciate Ligament Reconstruction Using Robotic Technology
Abstract The PCL consists of two primary bundles, the anterolateral (AL) and posteromedial (PM). The AL bundle is larger, stiffer, and has a higher ultimate load (Harner, 1995), and has been the focus of PCL replacement surgery (Clancy, 1983). However, clinical outcomes of PCL reconstruction have been unsatisfactory (Lipscomb, 1993); which has led to the question of the advancement of a double bundle procedure in hopes to more accurately reproduce the PCL (Clancy, 1998). It was therefore the objective of this study to evaluate the biomechanics of a double bundle PCL reconstruction (PCL-2), and compare these results with those obtained for the intact knee as well as a single bundle PCL reconstruction (PCL-1). To study this, a robotic/universal force-moment sensor (UFS) testing system which measures the multiple degree of freedom (DOF) knee kinematics determines the in situ force in the ligaments (or replacement grafts) in response to external loading conditions was utilized. The hypothesis was that PCL-2 would improve knee kinematics and in situ forces to those of the intact knee throughout the range of knee flexion as compared to PCL-1.