International Journal of Physical Medicine & Rehabilitation
Open Access

Abstract

Knee Biomechanics during Side-Step Cutting and Performance on Return to Sport Tests: Retrospective Analysis Following Anterior Cruciate Ligament Re- Injury

Pollard CD, Stearns-Reider KM, Mia Katzel and Landel RF

Objective: Re-injury rates following anterior cruciate ligament reconstruction (ACLR) are elevated compared to rates for initial anterior cruciate ligament (ACL) injury. The purpose of this study was to examine three-dimensional knee mechanics in an individual who had undergone an ACLR and then went on to re-injure that reconstructed ACL.

Methods: The primary subject was a female soccer player, 18 months post-ACLR, who then re-injured her ACL 3 months after biomechanical testing and return to sport (RTS) testing. We conducted 3-dimensional biomechanical testing of her knee mechanics and performance on return to sport (RTS) tests prior to her ACL re-injury. In addition, we compared her knee mechanics prior to re-injury to a control group of healthy female soccer athletes to determine if any biomechanical differences existed that may have indicated risk for ACL re-injury.

Results: Our findings indicate that altered lower extremity biomechanics, previously associated with increased risk of ACL injury, are present following ACLR and return to sports participation despite a lack of marked bilateral differences in performance on return to sport tests.

Conclusion: These findings are consistent with those in the literature suggesting that subjects’ post-ACLR may be adopting a strategy that minimizes loading at the knee joint. While it is not known if this biomechanical pattern increases the risk for a re-injury event, it suggests that there are deficits present following ACLR that may not be addressed with rehabilitation and recognized with RTS testing prior to return to sports participation. These findings point to an important gap in the literature with regards to clinical predictors of ACL re-injury.