With a spinal cord injury (SCI), damage can occur to the nerves that allow a person to control bowel movements.
There are two typical patterns of neurogenic bowel: “upper motor neuron” and “lower motor neuron.” Some people with SCI also have a mixed picture, with features of both.
A SCI may result in a loss of ability to feel when the rectum is full. Bowel movements occur reflexively when the rectum is full. This type of bowel problem is called an upper motor neuron or “reflexic bowel.” It can be managed by causing the defecation reflex to occur at a socially appropriate time and place.
A spinal cord injury level may damage the defecation reflex and relax the anal sphincter muscle. This is known as a lower motor neuron, “flaccid” or “areflexic” bowel. Management of this type of bowel problem may require more frequent attempts to empty the bowel and bearing down or manual removal of stool.
Both types of neurogenic bowel can be managed successfully to prevent unplanned bowel movements and other bowel problems such as constipation, diarrhea and impaction.
A spastic neurogenic bowel is caused when messages between the brain and the colon are interrupted (stopped) when a SCI is at the neck (cervical) or chest (thoracic) level.
A flaccid, or “limp” neurogenic bowel is caused by a spinal cord injury at the lumbar (lower back) or sacral (tail bone) area of the spinal cord. The nerves that go out from this area to the bowel also may have been damaged, decreasing the reflex (automatic) control of the anal sphincter.
The primary symptom of neurogenic bowel disease is a loss of bowel control, causing incontinence or constipation.
Diagnosis of a neurogenic bowel will include a full physical examination, including rectal examination in order to devise a bowel regimen. A neurologic examination can reveal the extent of the nerve damage and the completeness of the SCI.
When devising a bowel regimen, a patient’s upper and lower extremity strength, sitting balance, and ability to transfer, weight, and extremity length are taken into consideration
Complications of neurogenic bowel may include hemorrhoids, pain, diarrhea, impaction, or appetite loss.