Functional assessment and muscle strength before and after reconstruction of chronic anterior cruciate ligament lesions.

Purpose: The goal of this study was to evaluate strength and functional capacity before and after anterior cruciate ligament (ACL) reconstruction to determine the influences of preoperative strength deficit, graft type, and gender, as well as their clinical relevance in predicting postsurgical recovery and determining the postoperative rehabilitation program.

Methods: This was a retrospective review of prospectively collected uniform data from a group of 191 patients undergoing ACL reconstruction. We assessed functional capabilities and strength of the quadriceps and hamstring at 60 degrees/s and 180 degrees/s by use of a Cybex II dynamometer (Lumex, Ronkonkoma, NY) before and 6, 9, and 12 months after surgery.