Exploring the role of cognitive-motor function in biomechanical risk factors for primary and secondary anterior cruciate ligament injuries

Abstract

Non-contact anterior cruciate ligament (ACL) injuries continue to present major challenges in sports medicine, with long-term consequences for physical function and quality of life. A growing body of evidence indicates that these injuries frequently occur in dynamic environments where athletes must rapidly interpret visual cues and make decisions under pressure. Such cognitive demands may impair neuromuscular control and elevate injury risk, yet current screening and rehabilitation practices often fail to address the cognitive-motor processes that influence movement performance. This dissertation investigates how cognitive load alters biomechanical and neural mechanisms related to ACL injury risk in both healthy and ACL-reconstructed (ACLR) athletes. Dual-task paradigms integrating visual decision-making with jump-landing tasks were used to evaluate knee mechanics and cortical activation under increasingly complex conditions. Additionally, this work uniquely incorporates trials with unbalanced landings and incorrect responses, performance outcomes typically discarded in prior research, to better reflect real-world scenarios in which athletes fail to react appropriately. Through combined analysis of neuromuscular control, decision-making performance, and cortical activation, this research characterizes the interplay between cognitive demands and movement adaptation. Findings from this work advance a more comprehensive framework for ACL injury risk assessment and post-ACLR rehabilitation by highlighting the importance of cognitive-motor function in restoring safe and effective movement during challenging movements. Ultimately, this dissertation contributes evidence to support injury-prevention strategies and return-to-sport criteria that reflect the cognitive complexity of athletic environments.