Most anal fissures are caused by stretching of the anal mucosa beyond its capability. An anal fissure most often occurs when passing large or hard stools. Chronic constipation or frequent diarrhoea can also tear the skin around the anus. Other common causes of anal fissures include:

• Childbirth trauma in women
• Sexual activities
• Crohn’s disease
• Ulcerative colitis
• Poor toileting in young children
• Decreased blood flow to the anorectal area
• Overly tight or spastic anal sphincter muscle

An anal fissure may cause one or more of the following symptoms:

• Visible tear in the skin around the anus
• Skin tag, or small lump of skin, next to the tear
• Sharp pain in the anal area during bowel movements



• Burning or itching in the anal area
• Streaks of blood on stools or on tissue paper after wiping

Anal fissure is usually diagnosed simply by examining the area around the anus. However, digital rectal examination can also be performed to confirm the diagnosis. During this exam, the doctor will insert an endoscope or anoscope into your rectum to make it easier to see the tear. These medical instruments are thin tubes with attached cameras and lights that allow doctors to inspect the anal canal. Using an anoscope may also help your doctor find other causes of anal or rectal pain such as hemorrhoids.

Non-surgical treatments are recommended initially for acute and chronic anal fissures. These include topical nitroglycerin or calcium channel blockers (e.g. diltiazem), or injection of botulinum toxin into the anal sphincter. Other measures include warm sitz baths, topical anesthetics, high-fiber diet and stool softeners.

A sitz bath is a warm, shallow bath that cleanses the perineum.

Surgical procedures are generally reserved for people with anal fissure, who have tried medical therapy for at least one to three months and it has not healed. It is not the first option in treatment.

• Lateral internal sphincterotomy: LIS is the surgical procedure of choice for anal fissures due to its simplicity and its high success rate (~95%). In this procedure the internal anal sphincter is partially divided in order to reduce spasming and thus improve the blood supply to the perianal area. This improvement in the blood supply helps to heal the fissure, and the weakening of the sphincter is also believed to reduce the potential for recurrence. The procedure is generally performed as a day surgery after the patient is given general anaesthesia. The pain from the sphincterotomy is usually mild and is often less than the pain of the fissure itself. Patients often return to normal activity within one week.
• Fissurectomy: This is another surgery that can be used to treat anal fissures. This procedure produces the same result as a sphincterotomy, except that during this surgery, the edges of the fissure are also surgically removed, as are any skin tags that may have occurred in conjunction with chronic tears. A cauterising tool is then used to seal the entire area of the wound. The muscle is not cut.

• By keeping the anal area dry
• By cleansing the anal area gently with mild soap and warm water
• By drinking plenty of fluids, eating fibrous foods, and exercising regularly
• By treating diarrhoea immediately