INTRODUCTION

We are investigating the potential differences between a subject with a normal functioning anterior cruciate ligament (ACL) and a subject with a reconstructed ACL. Many athletes today undergo ACL reconstruction in the hopes that they will be able to perform at the same capacity as they did prior to the injury. However, research has shown that there are gait differences, such as reduced mid-stance knee flexion moments, after ACL reconstruction (Timoney et al., 1993). Therefore, it is valuable for us to study whether reconstructive surgery is effective in regaining normal knee range of motion.

Although subjects with reconstructed anterior cruciate ligaments usually function normally during light activities, such as walking, higher-demand activities reveal persistent functional abnormalities (Bush-Joseph et al., 2001). For our purposes, we have selected jogging because we believe it is a fairly demanding motion where any differences between the subjects will be more pronounced. We will be observing flexion and extension at the knee joint and range of motion of the shank segment. Our hypothesis is that the subject with the reconstructed ACL will have a smaller range of motion at the knee while jogging.