Rectal prolapse is a condition in which the rectum (the lower end of the colon, located just above the anus) becomes stretched out and protrudes out of the anus. Weakness of the anal sphincter muscle is often associated with rectal prolapse at this stage, resulting in leakage of stool or mucus. While the condition occurs in both sexes, it is much more common in women than men.
Several factors may contribute to the development of rectal prolapse. It may come from a lifelong habit of straining to have bowel movements or as a late consequence of the childbirth process. Rarely, there may be a genetic predisposition. It seems to be a part of the aging process in many patients who experience stretching of the ligaments that support the rectum inside the pelvis as well as weakening of the anal sphincter muscle. Sometimes rectal prolapse results from generalized pelvic floor dysfunction, in association with urinary incontinence and pelvic organ prolapse as well. Neurological problems, such as spinal cord transection or spinal cord disease, can also lead to prolapse. In most cases, however, no single cause is identified.
Some of the symptoms may be the same: bleeding and/or tissue that protrudes from the rectum. Rectal prolapse, however, involves a segment of the bowel located higher up within the body, while hemorrhoids develop near the anal opening.
A physician can often diagnose this condition with a careful history and a complete anorectal examination.
Occasionally, a rectal prolapse may be “hidden” or internal, making the diagnosis more difficult. In this situation, an x-ray examination called a video defecogram may be helpful. This examination, which takes x-ray pictures while the patient is having a bowel movement, can also assist the physician in determining whether surgery may be beneficial and which operation may be appropriate. Anorectal manometry may also be used to evaluate the function of the muscles around the rectum as they relate to having a bowel movement.
Although constipation and straining may contribute to the development of rectal prolapse, simply correcting these problems may not improve the prolapse once it has developed. There are many different ways to surgically correct rectal prolapse.
Abdominal or rectal surgery may be suggested. An abdominal repair may be approached laparoscopically in selected patients. The decision to recommend an abdominal or rectal surgery takes into account many factors, including age, physical condition, and extent of prolapse and the results of various tests.
A great majority of patients are completely relieved of symptoms, or are significantly helped, by the appropriate procedure. Success depends on many factors, including the status of a patient’s anal sphincter muscle before surgery, whether the prolapse is internal or external, and the overall condition of the patient. If the anal sphincter muscles have been weakened, either because of the rectal prolapse or for some other reason, they have the potential to regain strength after the rectal prolapse has been corrected. It may take up to a year to determine the ultimate impact of the surgery on bowel function. Chronic constipation and straining after surgical correction should be avoided.