An anal fissure is a small tear in the thin, moist tissue (mucosa) that lines the anus.

An anal fissure may occur when you pass hard or large stools during a bowel movement.

Anal fissures typically cause pain and bleeding with bowel movements. You also may experience spasms in the ring of muscle at the end of your anus (anal sphincter).

A lateral sphincterotomy involves making a small cut in the ring of muscle surrounding the sphincter to help reduce the tension in your anal canal. This allows the anal fissure to heal and reduces your chance of developing any more fissures.

An anal fissure is a small tear in the thin, moist tissue (mucosa) that lines the anus.

An anal fissure may occur when you pass hard or large stools during a bowel movement.

Anal fissures typically cause pain and bleeding with bowel movements. You also may experience spasms in the ring of muscle at the end of your anus (anal sphincter).

A lateral sphincterotomy involves making a small cut in the ring of muscle surrounding the sphincter to help reduce the tension in your anal canal. This allows the anal fissure to heal and reduces your chance of developing any more fissures.