What is rectal prolapse?Rectal prolapse is a condition in which the rectum, (the lower end of the colon, located just above the anus), turns itself inside out. Rectal prolapse is protrusion of rectal tissue through the anus to the exterior of the body. The rectum is the final section of the large intestine. In the earliest phases of this condition, the rectum does not stick out of the body, but as the
condition worsens, it may protrude.
Rectal prolapse can be either partial or complete. In partial prolapse, only the mucosa layer (mucous membrane) of the rectum extends outside the body. The projection is generally 0.75-1.5 inches (2-4 cm) long. In complete prolapse, called procidentia, the full thickness of the rectum protrudes for up to 4.5 inches (12 cm). Rectal prolapse is most common in people over age 60, and occurs much more frequently in women than in men. It is also more common in psychiatric patients. Prolapse can occur in normal infants, where it is usually transient. In children it is often an early sign of cystic fibrosis or is due to neurological or anatomical abnormalities.
Although rectal prolapse in adults may initially reduce spontaneously after bowel movements, it eventually becomes permanent. Adults who have had prior rectal or vaginal surgery, who have chronic constipation, regularly depend on laxatives, have multiple sclerosis or other neurologic diseases, stroke, or paralysis are more likely to experience rectal prolapse.
There are three types of rectal prolapse:
Mucosal prolapse (also called partial prolapse). Only the lining (mucous membrane) of the rectum slides out of place and usually protrudes from the anus when a person strains to have a bowel movement. The condition sometimes is confused with internal hemorrhoids. (See an illustration of a hemorrhoid.) Mucosal prolapse is most common in children younger than age of 2.
Complete prolapse. The entire wall of the rectum slides out of place and usually protrudes from the anus. At first, this may occur only during bowel movements. Eventually, the prolapse may occur upon standing or walking or may remain outside the body all the time.
Internal prolapse (intussusception). One part of the wall of the large intestine (colon) or rectum may slide into or over another part of the rectum, like the folding parts of a telescope. The rectum does not protrude outside the anus. Intussusception is most common in children and rarely affects adults. In children, the cause is usually not known. In adults, it is usually related to another intestinal problem.