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Anorectal Manometry


Anorectal manometry is a test used to evaluate the function and coordination of the internal and external sphincter and pelvic floor muscles. This test also records the measurement of resting and squeezing pressures in addition to the length of the anal canal. This test may also be used for pre-operative evaluations to assess sphincter function prior to rectal or anal surgery.

Anorectal manometry (also referred to by its abbreviation 'ARM') is a diagnostic test to measure the pressure exerted by the anal sphincter muscles and test how the nerves that supply the anal area are functioning. If the anal sphincter muscles do not contract when they should or if they are weak, then faecal incontinence can result.

Anal sphincter muscles normally relax when you are having a bowel movement, but if they are instead tightening, this may cause constipation. Anorectal manometry enables these functions to be measured.


This test is used in the diagnosis of:

  • Faecal incontinence.
  • Constipation.
  • Abnormalities of the anus.
  • Hirschprung disease (a rare disease of the bowels primarily affecting very young children).

Preparing for an anorectal manometry

Prior to your appointment for Diagnostic testing it is essential that you administer a Microlax enema 2 hours before your appointment. This will ensure that your bowels are completely empty for the testing. Microlax enemas are available from reception or can be purchased at your local pharmacy for approximately $5 each.

Patients having an anorectal manometry should take one or two 'Fleet enemas' 1-2 hours before the procedure (these are available to purchase at any pharmacy). You should also not eat anything in the two hours before the procedure. Any medication you have to take should be taken with very small sips of water at least two hours ahead of the procedure.

Do not take any muscle relaxant (this includes narcotic pain medication and other medication such as diazepam [Valium] or cyclobenzaprine [Flexeril]) in the 24-hour period before the procedure.


An anorectal manometry is conducted while the patient is awake, so no anaesthetic is required. The procedure takes 10-30 minutes. The patient lies down on his/her left side and the specialist performs a rectal examination. Then a thin, short flexible tube (a catheter) with a small 'balloon' on the end is inserted via the anus into the rectum. This balloon is connected to a machine to measure responses, and the patient may be asked to push or squeeze their anal muscles and also to say whether they are feeling any distension when the balloon is inflated.

The procedure may also involve an 'anal sphincter electromyograph' ('EMG') to measure the function of the nerves controlling the anal muscles and/or a 'balloon expulsion test', where a small balloon is inserted in the anus and filled with some water. The patient is then asked to go to the toilet and 'expel' the balloon. If it takes a long time for the balloon to be expelled, this indicates a problem in the function of the anorectal area.

The procedure may occasionally be uncomfortable, but there should be no pain at all.

Post Procedure Instructions

After the procedure you will be able to return home or return to work. Since no anasthetic is involved you can drive yourself to and from the appointment.


Anorectal manometry is a very low risk procedure. Very rarely indeed complications may develop, such as bleeding or perforation of the rectum. If you are allergic to latex you should inform the health team and a latex free balloon will be used.

Caring for patients across the Gold Coast

For your convenience, our surgeons perform procedures at several hospitals across the Gold Coast.

Call 07 5598 0955 to book a consultation with one of the dedicated surgeons at Core Specialist Group throughout locations across the Gold Coast, contact our friendly staff to enquire how we can best help you.