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Anal fissure - Symptoms
Last reviewed: 06.07.2025
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The most frequent localization of cracks (at 12 o'clock on the back wall and at 6 o'clock on the front) is explained by the peculiarities of the structure of the anal sphincter. It is at 6 and, especially, 12 o'clock that the worst conditions for blood supply exist, and there is a great risk of trauma to the mucous membrane when passing feces during the act of defecation due to pressure on the posterior and anterior commissures. Traumatization of the mucous membrane leads to acute pain due to irritation of numerous nerve endings and spasm of the sphincter. A vicious circle is formed - an anal fissure leads to a sharp pain syndrome, pain syndrome - to spasm of the sphincter, spasm of the sphincter prevents healing of the crack.
The symptoms of anal fissure are characterized by a triad of signs typical for the clinical picture of anal fissure: pain during and, especially, after defecation; sphincter spasm; scanty bleeding, different from the bleeding observed with hemorrhoids. There are some differences in the clinical picture of acute and chronic fissure.
In acute anal fissure, the symptoms are vivid. The main symptoms of anal fissure are acute pain that occurs after defecation and continues for several hours.
The spasm of the sphincter contributes to the increase of pain, makes it pulsating. Blood is detected in the form of drops on the surface of the feces.
Due to the spasm of the sphincter and the feeling of fear before the act of defecation, the stool is delayed. Taking laxatives increases the pain.
With a chronic anal fissure, the pain is less acute and lasts 5-10 minutes after a bowel movement. The sphincter spasm is weakly expressed. When a chronic anal fissure is complicated by marginal fistulas, purulent discharge, itching, and irritation of the perianal skin appear. A chronic fissure is characterized by a cyclical course. It can heal. However, with the slightest straining during defecation or physical exertion, it opens again.
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