Bowel and anal sphincter dysfunction

What is incontinence?
Incontinence is the impaired ability to control wind or stool. Its severity ranges from mild difficulty with wind control to severe loss of control over liquid and formed stools. Incontinence to stool is a common problem, with an estimated prevalence of 4 people in every 1000 rising to more than 10 people in every 1000 above the age of 65 age. It is more common in women and in the elderly of both sexes.

Many people with faecal incontinence are ashamed to talk about this problem with their doctor. They think that nothing can help them. However, many effective treatments for faecal incontinence are available.

How is continence achieved?
Bowel function and continence is controlled by three factors: anal sphincter pressure, rectal storage capacity and rectal sensation. The anal sphincter is a muscle that contracts to prevent stool from leaving the rectum. This muscle is critical in maintaining continence. The rectum can stretch and hold stool for some time after a person becomes aware that the stool is there. This is the rectal storage capacity. Rectal sensation tells a person that stool is in the rectum. Then the person knows that it is time to go to the bathroom. A person also must be alert enough to notice the rectal sensation and do something about it. He or she must also be able to move to a toilet. If something is wrong with any of these factors, then faecal incontinence can occur.

What causes incontinence?
Muscle damage is involved in most cases of faecal incontinence. In women, this damage commonly occurs during childbirth. It's especially likely to happen in a difficult delivery that uses forceps and/or an episiotomy. An episiotomy is when a cut is made to enlarge the opening to the vagina for delivery of a baby. A young woman can often compensate for muscle weakness. Typically, they only develop incontinence in later life when their muscles are growing weaker and the supporting structures in the pelvis are becoming loose. Muscle damage can also occur during anal surgery (especially surgery for piles or deep fistulae). It may also occur in people with inflammatory bowel disease or an abscess in the perianal area.

Damage to the nerves that control the anal muscle or that are responsible for rectal sensation is also a common cause of fecal incontinence. Nerve injury can occur in the following situations:

  • During childbirth.
  • With severe and prolonged straining for stool (chronic constipation).
  • With diseases such as diabetes, spinal cord tumors and multiple sclerosis.

Incontinence may also be caused by a reduction in the elasticity of the rectum, which shortens the time between the sensation of the stool and the urgent need to have a bowel movement. Surgery or radiation injury can scar and stiffen the rectum. Inflammatory bowel disease can also make the rectum less elastic.

Because loose stool (diarrhea) is more difficult to control than formed stool, diarrhea is an added stress that can lead to fecal incontinence. A change in stool consistency to a looser form often causes the problem of incontinence to show up. If bleeding accompanies lack of bowel control, This must be reported promptly. These symptoms may indicate inflammation within the colon (colitis), a rectal tumor, or rectal prolapse - all conditions that require thorough evaluation.

How is the cause of incontinence determined?
An initial discussion of the problem will help establish the degree of control difficulty and its impact on your lifestyle. Many clues to the origin of incontinence may be found in patient histories. For example, a woman's history of past childbirths is very important. Multiple pregnancies, large weight babies, forceps deliveries, or episiotomies may contribute to muscle or nerve injury at the time of childbirth. In some cases, medical illnesses and medications play a role in problems with control.

Afterwards an examination of the anal and vaginal region is performed. It may readily identify an obvious injury to the anal muscles. It will also identify any weakness in the vaginal area which often are present and usually caused by the same mechanism that lead to the anal weakness.

To obtain an objective evidence of the extent of the weakness, additional studies are required. These help to define the anal area more completely and use it as a base line to monitor treatment progress. Anal manometry, is a test where a small catheter is placed into the anus to record pressure as patients relax and tighten the anal muscles. This test can demonstrate how weak or strong the muscle really is. Pudendal nerve latency is another test, which determines if the nerves that go to the anal muscles are functioning properly. Endoanal ultrasound scan involves inserting probe within the anal area to provide a picture of the muscles and show areas in which the anal muscles have been injured. Finally, proctogram is another test that may be done to look at the configuration of the rectum especially if there is associated history of constipation.

What can be done to correct the problem?
After a careful history, physical examination and testing to determine the cause and severity of the problem, treatment can be addressed. Mild problems may be treated very simply with dietary changes and the use of some constipating medications. In addition, simple home exercises that may strengthen the anal muscles may help in mild cases.

In other cases, biofeedback can be used to help patients' sense when stool is ready to be evacuated and help strengthen the muscles. Injuries to the anal muscles may be repaired with surgery (sphincter repair). Diseases, which cause inflammation in the rectum, such as colitis, may contribute to anal control problems. Treating diseases such as colitis or rectal prolapse may eliminate or improve symptoms of incontinence. Sometimes a change in prescribed medications may help.

New research is currently evaluation the use of topical ointments as well as new surgical techniques such transposing and wrapping gracilis muscle around the anus or insertion of artificial sphincter. In the past, patients with no hope of regaining bowel control required a colostomy. Today, this procedure is rarely required.


Diverticular disease
Ulcerative Colitis
Crohns disease
Irritable bowel syndrome
Rectal prolapse
Bowel and anal sphincter dysfunction
Anal fissure
Anal abscess & fistula
Anal Warts
Colonic polyps
Familial adenomatous polyposis
Pilonidal sinus
Bowel obstruction

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