What is the cause of anal relaxation? How is it caused?

The causes of anal relaxation can be divided into two main categories. One is congenital factors, that is, some people experience anal relaxation due to congenital malformations. The other is acquired and man-made, such as women giving birth and damage to the perianal muscles.

1. Congenital factors

Congenital anorectal malformations or neurological disorders can lead to anal relaxation. The congenital factors in children are that the pelvic tissue structure is not fully developed, and the surrounding tissue supporting the rectum is relatively weak and not firmly fixed.

2. Fertility factors

Perineal lacerations during childbirth can completely rupture the anal sphincter and cause anal relaxation.

3. Anal muscle injury

It is mainly anal sphincter injury, which is caused by anorectal surgery, such as inadvertent damage during surgery for perianal abscess, anal fistula, internal and external hemorrhoids, etc. Or the anus may become loose due to external injuries, such as external impact, burns, frostbite, tearing, etc.

4. Anorectal diseases

The most common are rectal tumors and inflammatory diseases. Rectal tumor infiltration damages the anal sphincter, ulcerative colitis causes rectal inflammation leading to long-term diarrhea, and complete rectal prolapse causes anal relaxation. In addition, scarring from burns in the anus or damage caused by drug corrosion can also cause anal relaxation.

5. Anal sphincter dysfunction

Due to the presence of anorectal diseases such as mixed hemorrhoids and annular internal hemorrhoids, the anal sphincter expands and relaxes excessively; or due to old age and physical weakness, the anal sphincter atrophies and becomes weak, resulting in sphincter dysfunction and anal relaxation. In addition, neurological diseases such as anal nerve damage, spinal cord and sacral nerve damage, and infection can also cause sphincter dysfunction.