Briefly about anal fissure
An anal fissure is a tear in the lining mucous layer) of the lower rectum and anal canal that causes pain during bowel movements. It is a common condition. Anal fissures do not lead to more serious conditions.

In most of the cases anal fissures heal with home treatment (like local ointments, suppositories), after a few weeks (these are called acute anal fissures).

If you have an anal fissure that has not healed after 6 weeks, it is considered a long-term problem as chronic anal fissure. You may need to take medicine like nitro-glycerine local ointment, to help a chronic anal fissure heal. Surgery may be necessary for fissures that do not heal with medicine.

Symptoms that are very often experienced with anal fissure:
Pain or burning during bowel movements that usually eases until the next bowel movement
Bright red blood on the outside of the stool or on toilet paper after a bowel movement
Itching or irritation of the anus
A visible crack in the skin around the anus

What causes an anal fissure?
Anal fissures are caused by injury (trauma) to the anal canal. Injury can happen if:
You pass a large stool that stretches the anal canal.
You are constipated and try to pass a hard stool.
You have repeated diarrhea.
Inflammation of the anorectal area, such as is caused by inflammatory bowel disease (IBD)
Anal sex, less commonly

Treatment
In most of the cases anal fissure easily can be treated locally with ointments, suppositories, and keeping stools soft and loose.
You may only need to consider surgery if medicines do not stop your symptoms. In this case you have a chronic anal fissure that won`t heal on it`s own.
Surgery of anal fissure
The most commonly used surgery is lateral internal sphincterotomy. In this procedure, a doctor carefully cuts into part of the internal sphincter to relax the spasm that is causing the fissure. Surgery may also include removal of the fissure and any scar tissue resulting from it.
Usually done in day surgery, or in case of uncontrollable postoperative pain an overnight stay in hospital may be necessary.

Complications are extremely rare:
Minor bleeding
Rarely, cutting the anal sphincter results in loss of ability to control bowel movements.
Rarely headache after regional anaesthesia

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