Neurocognitive and Neurophysiological Functions Related to ACL Injury: A Framework for Neurocognitive Approaches in Rehabilitation and Return-to-Sports Tests

Abstract

Context: Only 55% of the athletes return to competitive sports after an anterior cruciate ligament (ACL) injury. Athletes younger than 25 years who return to sports have a second injury rate of 23%. There may be a mismatch between rehabilitation contents and the demands an athlete faces after returning to sports. Current return-to-sports (RTS) tests utilize closed and predictable motor skills; however, demands on the field are different. Neurocognitive functions are essential to manage dynamic sport situations and may fluctuate after peripheral injuries. Most RTS and rehabilitation paradigms appear to lack this aspect, which might be linked to increased risk of second injury. Objective: This systematic and scoping review aims to map existing evidence about neurocognitive and neurophysiological functions in athletes, which could be linked to ACL injury in an integrated fashion and bring an extensive perspective to assessment and rehabilitation approaches. Data Sources: PubMed and Cochrane databases were searched to identify relevant studies published between 2005 and 2020 using the keywords ACL, brain, cortical, neuroplasticity, cognitive, cognition, neurocognition, and athletes. Study Selection: Studies investigating either neurocognitive or neurophysiological functions in athletes and linking these to ACL injury regardless of their design and technique were included. Study Design: Systematic review. Level of Evidence: Level 3. Data Extraction: The demographic, temporal, neurological, and behavioral data revealing possible injury-related aspects were extracted and summarized. Results: A total of 16 studies were included in this review. Deficits in different neurocognitive domains and changes in neurophysiological functions could be a predisposing risk factor for, or a consequence caused by, ACL injuries. Conclusion: Clinicians should view ACL injuries not only as a musculoskeletal but also as a neural lesion with neurocognitive and neurophysiological aspects. Rehabilitation and RTS paradigms should consider these changes for assessment and interventions after injury.

Return to sports after ACL injury 5 years from now: 10 things we must do

“…Unfortunately, sensorimotor control of the injured lower extremity may appear to rely on visual information processing and cortical motor planning [ 89 ]. This, in turn, may limit the individual’s capacity to manage complex motor situations and subsequently predispose ACLR patients to recurrent injury after their return-to-sports [ 83 , 98 ].…”

“…Current rehabilitation programs may not effectively target aberrant movement patterns after ACLR [ 50 , 98 ]. In light of the aforementioned CNS changes, Gokeler et al [ 49 ] posited that rehabilitation in patients after ACL injury should ideally include sensory and cognitive variations in order to reduce dependency on visual information and in turn facilitate the ability of the brain to achieve novel strategies to cope with altered afferent information from the knee joint.…”

Think outside the box: Incorporating secondary cognitive tasks into return to sport testing after ACL reconstruction

“…In the case of an individual returning to sport after ACLR, compensatory neural strategies may lead to more difficulty for these athletes in dual-task scenarios, potentially increasing risk of a second ACL injury ( 78 ). Therefore, screening for ACL injury risk, including second ACL injury risk following ACLR, should include tasks that incorporate dual-tasks.…”

Cortical Changes as a Result of Sports Injuries: A Short Commentary

“…Under the sports neuroscience paradigm, we understand how the integration of neuromechanics allows for a better comprehension of human movement (Piskin et al, 2021). This field seeks to understand how the muscular system interacts with the brain to produce coordinated movements in complex and unexpected situations (Nishikawa et al, 2007;Seidel-Marzi & Ragert, 2020).…”