Rectal Prolapse

Rectal prolapse is the condition when full-thickness (all layers) of the rectum slides down, often out of the anus when noticed. This occurs when there is weakening of the pelvic floor. Pelvic floor is a group of muscles and connective tissues that work together to support the organs in the pelvis including the anus and rectum, bladder, uterus and vagina. When the pelvic floor is weak, it is not be able to support the pelvic organs, which then sink downward by gravity (prolapse). Weakness may be due to aging, previous multiple childbirths, chronic constipation and straining, or previous pelvic surgery (e.g. hysterectomy). A rectum prolapsing through the anus may stretch the anal sphincter and weakens it further, causing fecal incontinence and allowing the rectum to prolapse further. Rectal prolapse sometimes co-exist with pelvic organ prolapase, which refers to prolapse of the bladder and/or uterus into the vagina. Rectal prolapse is not the same as prolapsed hemorrhoids and anal mucosal prolapse. The latter two are prolapse of the inner lining (mucosa) and the connective tissue layer (submucosa, where the hemorrhoidal blood vessels live) of the anal canal. They are not full-thickness prolapse and does not involve the rectum.

Types and symptoms of rectal prolapse

Rectal prolapse may occur to varying degree. When the prolapse become external (the rectum is out), symptom is more severe.

  • Complete rectal prolapse - the rectum prolapses externally out of the anus. In the earlier stage, the prolapse may go back in on its own spontaneously. As the prolapse get worse, the rectum may only go back in when patient lies down or manually pushes it back in, and does not stay in for long. Typical associated symptoms include anorectal pain, mucus and blood in stool or on underwear, fecal incontinence, sensation of constipation (due to prolapsed bulge blocking stool passage).

  • Rectal intussusception (internal prolapse) - the rectum prolapses down into the lower rectum itself or the anal canal but stays internally. Patient may complain of sensation of constipation, rectal or pelvic pain and discomfort, blood and/or mucus with bowel movement.

The lining of the rectum normally looks and feels like the inside of your lips and mouth - pink and moist. When the rectum is prolapsed and gets swollen, it becomes more bright red color and the trauma of it going in-and-out causes the lining to slough, produce more mucus and sometimes bleed. When the rectum gets really swollen, it may be impossible to push it back in and you need to seek medical attention immediately (or better before this happens!) The swelling can cut off the blood supply to the rectum and you may need an emergency surgery.

Diagnosis of rectal prolapse

Rectal prolapse that is external can be diagnosed by visual exam. A detail history and physical exam also evaluate for any pre-existing constipation, co-exisitng pelvic organ prolapse, and exclude other more serious cause of prolapse such as colorectal polyps or cancer. Internal prolapse may need additional testing to confirm, typically a MRI defecography.

Treatment of rectal prolapse

Rectal prolapse is treated with surgery. When the rectum is prolapsed, it is safe and advisable to push the rectum back in yourself as a temporizing measure. To do this, lie down on your side and use few fingers to apply pressure and gently push it back in, do not use any sharp object. Although surgery is not emergent, it should be done sooner than later. This is because the prolapse will not get better without surgery, and the more and longer duration the anal sphincter is stretched by the prolapse, the less likely the anal sphincter function can "bounce back" after surgery (i.e. the fecal incontinence may not get much better after surgery). Surgery may be done through the abdominal approach (typically done laparoscopic/minimally invasive), or through the anus. In the abdominal approach, general anesthesia is required, the rectum is pulled back up and anchored to the sacrum bone. Sometimes mesh is used to reinforce the repair. In cases where there is pre-existing constipation, a partial colon resection may be performed. Surgery when done through the anus may not require general anesthesia. The prolapsed rectum is pulled out and resected, the cut end is then sutured to the anus, removing the redundancy. Choice of the procedure depends on your overall physical condition (how well you can tolerate anesthesia), the severity of prolapse, and whether you had previous colorectal surgery.

Helpful links:


*American Society of Colon and Rectal Surgeons