What causes an anal fissure?
What causes an anal fissure?
Anal fissures can be caused by trauma to the anus and anal canal. The trauma can be caused by one or more of the following:
- Chronic (long-term) constipation
- Straining to have a bowel movement, especially if the stool is large, hard and/or dry
- Prolonged diarrhea
- Anal sex, anal stretching
- Insertion of foreign objects into the anus
Causes other than trauma include:
- Longstanding poor bowel habits
- Overly tight or spastic anal sphincter muscles (muscles that control the closing of the anus)
- Scarring in the anorectal area
- An underlying medical problem, such as Crohn's disease and ulcerative colitis (types of inflammatory bowel disease); anal cancer; leukemia; infectious diseases (such as tuberculosis); and sexually transmitted diseases (such as syphilis, gonorrhea, Chlamydia, chancroid, HIV)
- Decreased blood flow to the anorectal area
Anal fissures are also common in young infants and in women after childbirth.