The rectum is located at the last few inches of the large intestine (colon).
The anal sphincter surrounds the anus and controls the release of stool, thereby maintaining continence.
There are two muscles: the internal anal sphincter and the external anal sphincter.
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This article will go over the anatomy of the anal sphincter and its function.
The lower part of the rectum is the anal sphincter.
The anal sphincter consists of two muscles:
Thepudendal nerveis a major nerve in the pelvis.
It tells the muscles that control pelvic organs and genitals to move.
This is calledanal sphincter innervation.
This response is also called the defecation reflex.
The internal anal sphincter and external anal sphincter work together to produce a bowel movement but in different ways.
If there is a loss of muscle control in the sphincter muscles,fecal incontinencemay occur.
It is more common in Crohn’s disease than in ulcerative colitis.
Other symptoms include pain and bleeding.
Anal stenosis can occur after surgeryespecially hemorrhoid removalor be associated with laxative overuse or infections.
This condition may be treated with stool softeners or fiber supplements.
Surgery to correct the problem may also be necessary.
Anismus
Anismusis a functional disorder of the pelvic floor muscles, including the external anal sphincter.
It is because of a problem with the way these muscles contract and relax during defecation.
Symptoms of anismus include:
Anismus is often treated with pelvic floor exercises.
Injections of Botulinum toxin (Botox) can also help.
Anal Fissure
An anal fissure is a tear in the lining of the anus.
Anal fissures often extend into the internal anal sphincter.
Symptoms of an anal fissure include pain and/or a sensation of tearing during a bowel movement.
There may be bright red blood in the toilet or on the toilet paper.
These symptoms usually occur with every bowel movement.
Anal fissures may be treated with topical medications, medications that help relax the sphincter muscle, or surgery.
This birth defect causes the anus to develop abnormally.
Surgery is required to correct them.
In many cases, antibiotics are prescribed to treat infection, and surgery is sometimes also necessary.
Hemorrhoids (Piles)
Ahemorrhoidis a vein around the anus that becomes swollen.
Hemorrhoids can be internal or external.
Internal hemorrhoids are above the internal anal sphincter.
External hemorrhoids are below the external anal sphincter.
Sometimes, the internal anal sphincter traps hemorrhoids.
This condition is called strangulated hemorrhoids and can be very painful.
Hemorrhoids can usually be managed at home with topical medication and regular sitz baths.
Surgery is often the best way to correct a strangulated hemorrhoid.
A damaged anal sphincter might need to be fixed with surgery.
When these muscles become damaged, you may have difficulty controlling your bowel movements.
These conditions range from mild to severe.
Some can be corrected with home care while others require surgery.
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