Exoskeleton Robot Gait Training and Its Impact on the Gut Microbiota-Brain Axis in Incomplete Spinal Cord Injury Patients: A Narrative Review of Rehabilitation Mechanisms.

Exoskeleton robot-assisted gait training represents a significant advancement in neurorehabilitation for patients with incomplete spinal cord injury (iSCI). While its efficacy in improving motor function is increasingly documented, emerging evidence suggests these interventions may exert therapeutic effects through previously unrecognized physiological pathways involving the gut microbiota-brain axis. This review synthesizes current evidence regarding the bidirectional relationship between exoskeleton-based locomotor training and alterations in gut microbiome composition and function in the context of iSCI. Following spinal cord injury, significant dysbiosis occurs, characterized by reduced microbial diversity and altered taxonomic representation, which correlates with neuroinflammation, autonomic dysfunction, and impaired recovery. Exoskeleton-mediated gait rehabilitation appears to partially restore microbial homeostasis through multiple mechanisms, including autonomic nervous system regulation, altered intestinal transit time, modified intestinal barrier integrity, and immunomodulation. These microbiome modifications potentially facilitate neuroplasticity and functional recovery through microbiota-derived metabolites that traverse the blood-brain barrier or communicate via vagal afferents. The integration of metagenomic analysis with functional neuroimaging and detailed autonomic assessment in prospective studies represents a critical research direction. This emerging perspective extends beyond biomechanical rehabilitation, suggesting a comprehensive neurobiological effect that includes modulation of the microbiota-gut-brain axis, with significant implications for optimizing therapeutic strategies for individuals with incomplete spinal cord injury.