Acute Genital Nerve Stimulation for Neurogenic Bowel Dysfunction in Individuals Living With Spinal Cord Injury

Electrical stimulation applied to the genital nerve with surface electrodes using an off the shelf TENS unit (Ultima Plus). First, an amplitude threshold for the pudendo-anal reflex responses will be determined. Then, sham (1-2 Hz) and effective stimulation (20 Hz) will be briefly applied to record responses. Then, stimulation will be applied in random presentation order to record any changes in anorectal manometry outcomes due to both sham and effective stimulation.

Examination by physician determines the presence of pelvic reflexes (pudendo-anal and bulbocavernosus) which are essential for GNS to have an effect.

Data regarding participant demographics, history of injury, and medical history will be collected.

Two surveys will be conducted to assess the bowel function of the participant. The International SCI Bowel Function Basic Data Set (ISCI BF BDS v2.1) and the SCI Qulaity of Life Bowel Management Difficulties (SCI-QoL BMD) survey scales collect data on overall bowel function and how any difficulties impact the participants quality of life.

The physician will conduct the ISNCSCI to determine the level and severity of injury to the spinal cord. This is done by determining the ability to detect light touch and pinprick stimulation. Outcomes will be a Spinal Injury Association Impairment Scale (AIS) grade of A-D.

GNS will be applied to determine if there is a response in the participant. If the participant has no response to the stimulation they will be excluded from the second visit as it is dependent on the ability to respond to GNS.

"The participant will be instrumented for ARM testing. This requires a special balloon catheter to be inserted into the anus and secured, surface electrode pads being applied to the anal sphincter, and electrode pads being applied to the genital nerve stimulation sites.~Once instrumented, the participant will be tested with the London Classification procedure. This procedure asks the participant to perform several actions (squeeze to withhold a bowel movement, push to have a bowel movement, and cough) as well as inflating the balloon on the catheter to determine reflex thresholds (RAIR, retroanal inhibitory reflex which relaxes the anal sphincter in response to rectal distension) and sensory thresholds (first senstation,"