Disrupted sensorimotor control after ACL injury: from mechanoreceptor degeneration to neuroplasticity-oriented rehabilitation

Abstract

Background: Anterior cruciate ligament (ACL) injury is one of the most common sports-related injuries, often resulting in not only mechanical instability but also long-term proprioceptive dysfunction. The ACL is richly innervated with mechanoreceptors that contribute to sensorimotor control. Injury-induced degeneration of these receptors leads to disrupted afferent signaling and maladaptive central nervous system (CNS) responses, which can compromise functional recovery and increase the risk of reinjury. Objective: This review aims to summarize current knowledge on ACL-associated proprioception, including mechanoreceptor anatomy, injury-induced changes in neural signaling, and advances in evaluation and rehabilitation techniques. Emphasis is placed on the integration of peripheral and central mechanisms and their implications for clinical interventions. Content: We detail the types and distribution of mechanoreceptors within the ACL and describe how their disruption alters joint position sense and kinesthesia. We further explore CNS neuroplasticity, such as cortical reorganization and bilateral sensorimotor changes. Traditional and emerging methods for proprioceptive assessment are critically evaluated. Finally, we discuss surgical and rehabilitative strategies—including remnant-preserving reconstruction, neuromuscular training, and neurofeedback—that target proprioceptive recovery through neuroplastic adaptation. Conclusion: Restoration of proprioceptive integrity following ACL injury requires a multifaceted approach that addresses both peripheral mechanoreceptor preservation and central sensorimotor reorganization. Future research should focus on standardized assessments, long-term neurophysiological monitoring, and the integration of sensor-based technologies to support individualized, neuroplasticity-driven rehabilitation strategies.