Apart from perhaps proctalgia or rectal pain, chronic constipation or diarrhea are the most common symptoms of bowel dysfunction seen in the PPOD syndrome patient. When part of the PPOD syndrome, these two symptoms reflect dichotomous states of neurologic dysfunction caused by an underlying mechanical disorder of the spine. In the case of constipation there is usually a reduction of the activity (inhibition) of the sensory and/or motor fibers that connect to and mediate control of the function of the large bowel and rectum. As a result, in the presence of sensory fiber impairment, there can be insufficient sensory stimulation to reinforce the normal peristaltic reflex that moves fecal matter through the colon. If motor fiber impairment predominates yet sensory fiber function is intact, there may be sufficient sensory stimulation to facilitate the peristaltic reflex, however, the motor fibers may be incapable of conveying the impulses associated with this reflex to the muscular wall of the colon in order to reinforce the peristaltic waves that move fecal matter through the colon. In either case, the net result is a neurogenic type of constipation that can be very severe and typically will not respond to dietary manipulation, vitamin and mineral supplementation or any of the typical types of chemical cathartic agents taken orally or intra-rectally. However, when constipation exists as part of the PPOD syndrome it usually demonstrates a dramatic response to PPOD syndrome therapeutic protocols. Refer to cases 3, 4, 5, 8, 9 and 10 for the response of chronic constipation to PPOD syndrome treatment.
In the case of chronic or recurrent diarrhea in the PPOD syndrome patient the situation is effectively the reverse of that of constipation. The underlying abnormality is one in which there is a state of hyperactivity (facilitation) of the function of the sensory and/or motor fibers that mediate control over the function of the large bowel and rectum. Whether this hyperactivity involves the sensory fibers, motor fibers or both, the net result is the same. There will be excessive colonic activity with exaggerated peristaltic action leading to frequent, loose, watery stools which may be accompanied by excessive gas and mucus discharge. Refer to case number 16 for the response of chronic diarrhea to PPOD syndrome treatment.