Clinical and Physiological Characterization of Neurogenic Bowel Dysfunction In Motor-Incomplete Spinal Cord Injury

BACKGROUND: Neurogenic bowel dysfunction is highly prevalent after spinal cord injury and significantly affects quality of life. The pathophysiology in motor-incomplete spinal cord injury remains poorly characterized, despite the availability of physiological tests, such as high-resolution anorectal manometry and colonic transit time. OBJECTIVE: To characterize clinical presentation, high-resolution anorectal manometry findings and colonic transit time in motor-incomplete spinal cord injury, and to compare patients with neurological level ≥ T6 versus < T6. DESIGN: Prospective cross-sectional study. SETTINGS: Specialized neurorehabilitation center. PATIENTS: Fifty-eight consecutively recruited patients with motor-incomplete spinal cord injury (72.4% men; mean age, 51.3 ± 16.3 years) were included. traumatic etiology was present in 39.7% of cases, with a mean time since injury of 3.9 ± 1.3 months. A neurological level ≥ T6 was observed in 58.6%. MAIN OUTCOME MEASURES: Clinical bowel characteristics, colonic transit time measurement and high-resolution anorectal manometry (International Anorectal Physiology Working Group Protocol, London Classification), and their associations. RESULTS: Eighty-one percent of patients had fecal incontinence, constipation, or both. prolonged colonic transit time was observed in 50%, without clear correlation with symptoms. high-resolution anorectal manometry showed a preserved rectoanal inhibitory reflex in all cases. According to the london classification, the most common abnormalities were anal hypocontractility, with or without anal hypotension (63.8%), rectoanal coordination disorders (56.9%) and rectal hyposensitivity (60.3%). No consistent associations were found between physiological findings, symptoms and neurological characteristics. LIMITATIONS: Treatment during assessment, limited normative high resolution anorectal manometry data, small subgroups, and lack of a control group. CONCLUSIONS: Neurogenic bowel dysfunction in motor-incomplete spinal cord injury shows substantial pathophysiological heterogeneity, frequently combining anorectal dysfunction and delayed colonic transit time. This may explain the limited ability of symptoms and neurological characteristics to identify underlying mechanisms and supports systematic physiological testing to guide mechanism-oriented management. See Video Abstract.