Stimulation for Colonic Motility

The investigators are testing the effect of electrical stimulation of the rectum on colonic motility. Most individuals with spinal cord injury develop neurogenic bowel dysfunction, which includes slowed colonic motility, which means that stools take longer than normal to pass through the colon. This slowed movement may result in chronic constipation and difficulty emptying the bowels. Individuals typically (without or without caregiver assistance) insert a gloved finger into the rectum and gently stretch it to improve colonic motility for a brief period to empty the bowels. The investigators hypothesize that electrically stimulating the rectum, instead of mechanically stretching it, will produce the same beneficial effect of improving colonic motility. Therefore, this study will compare the two methods. If electrical stimulation effectively improves colonic motility, then the investigator shall develop the approach as a therapeutic intervention in future studies.

Study participants will act as their own controls, first providing data using their usual digital rectal stimulation intervention for bowel care, then providing data using electrical stimulation for bowel care.

Electrical stimulation of the rectum will be applied to activate sensory afferent neurons of the rectum and evoke a recto-colonic reflex to improve colonic motility. This intervention will compared to individuals' usual mechanical intervention of digital rectal stimulation.

Compare Changes in Number of Interventions Used to Complete Bowel Routine, Including Electrical Rectal Stimulation (Treatment) Versus Mechanical Rectal Distension (Control)

Two interventions will be tested, including the clinical standard of digital rectal stimulation and a novel approach using electrical stimulation of rectal sensory afferents, to determine the effect on colonic pressure. Typically several bouts of digital rectal stimulation are required to achieve complete bowel emptying. We will compare the number of bouts of digital rectal stimulation (control) with electrical rectal stimulation (treatment) required to achieve complete bowel emptying.

Inclusion Criteria: Diagnosed neurogenic bowel dysfunction and using digital rectal stimulation Neurologically stable Skeletally mature Suprasacral spinal cord injury, stroke, or multiple sclerosis At least 6 months post neurological injury or disease diagnosis Exclusion Criteria: Active sepsis Open pressure sores on or around pelvis Significant colon trauma or colostomy History of autonomic dysreflexia