Dyssynergic defecation

What is dyssynergic defecation?

Dyssynergic defecation is a condition that affects the pelvic floor muscles. These are muscles located in the lower abdomen that allow bowel movements to pass normally. The pelvic floor muscles do this by supporting organs such as the rectum, uterus and bladder.

Dyssynergic defecation occurs when the pelvic floor muscles are unable to coordinate with the surrounding muscles and nerves to produce a normal bowel movement. This leads to constipation. About a quarter of chronic constipation is due to dyssynergic defecation.


Some patients develop dyssynergic defecation as children, some after an episode of pregnancy or injury, and others develop the condition without a known cause. Specifically, the cause of dyssynergic defecation is not clear.

The inability to coordinate muscle use is caused by impaired rectal contraction or paradoxical contraction. This is when the anal muscles either do not relax enough or tighten instead of relax during defecation. 

Many patients with dyssynergic defecation have decreased sensation in the rectum and trouble perceiving the arrival of a stool.


Symptoms of dyssynergic defecation are generally symptoms of constipation and can differ from patient to patient. Constipation also has a variety of causes and related conditions. If you are experiencing symptoms out of the ordinary you should visit a health care provider.

Common symptoms

  • Excessive straining while passing a stool
  • The passage of hard stools
  • A feeling of incomplete evacuation or that a stool is “stuck”
  • Less than three bowel movements per week
  • Using digital maneuvers (fingers) to have a bowel movement


If you are experiencing symptoms of dyssynergic defecation your doctor may begin with a digital rectal examination to rule out some causes of constipation such as anal hemorrhoids, strictures, or fissures. Your doctor will perform this test by examining the rectum by hand, with a lubricated glove.

If dyssynergic defecation is still suspected your doctor can recommend a variety of tests.

Blood tests- Examining a blood sample can give doctors a large amount of information about your overall health. This is useful in ruling out certain conditions and pointing doctors in the right direction by suggesting where possible issues may be.

Sigmoidoscopy- Using a small, flexible, lighted tube to exam your colon and rectum can allow doctors to rule out a wide variety of conditions. A biopsy (a sample of tissue taken for testing) can also be taken during this exam.

Colonic transit time exam- Testing the speed which stool moves through the colon can give doctors better insight into what may be the cause of your symptoms. This exam is conducted by swallowing a capsule containing markers and taking x-rays over several days.

Anorectal manometry- Testing the strength and weakness of the anal muscles is necessary for the diagnosis of dyssynergic defecation. This exam can also test the sensation and reflex ability of the rectum.

Balloon expulsion- By examining the opening of the anus and relaxation of the pelvic floor muscles, this exam can diagnose dyssynergia. The test is performed by placing a balloon in the rectum and seeing how it is expelled.

Defecography- Using x-rays and a semi-solid barium paste, doctors can see an imitated stool as it changes and passes through the rectum. The barium paste is inserted in the rectum, and moving images can be recorded with x-rays.

Multiple criteria must be met to diagnose dyssynergic defecation.


Treatment plans for dyssynergic defecation will be different from person to person. The condition is difficult to treat and may require episodes of trial and error. It is important your doctor addresses any coexisting issues that may make symptoms worse as well as when and how often bowel movements should be attempted. Your doctor may also recommend certain dietary and lifestyle guidelines to improve symptoms. Patients will often benefit from physical therapy for the pelvic floor muscles and biofeedback. Biofeedback therapy helps patients increase control of their body functions and promotes relaxation.   

Last reviewed: 
October 2018

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