ANAL FISSURE - a patient's guide
The Oxford Clinic

What is an anal fissure?

An anal fissure is a common disorder which affects any age group.

An anal fissure is a benign superficial ulcer in the anal canal. It is usually about 1cm long and at its lower end there may be a tag of swollen skin. This tag is called a sentinal pile. Sentinal, because it guards the fissure.

Primary fissures may be acute (sudden onset) or chronic (persistent symptoms of more than a few weeks).

What is the cause?

Most anal fissures arise following trauma (injury) to the anus. The most common trauma is associated with the passage or a hard, constipated stool. However, anal fissures can occur during bouts of diarrhoea, childbirth, or ulceration of thrombosed haemorrhoids.

More rarely it may present as a symptom of inflammatory bowel disease.

An anal fissure is a simple mechanical problem and does not turn to cancer.

What are the symptoms?

Pain is the major symptom of an anal fissure. It comes on at the time of defaecation and lasts for a variable period afterwards. It is mainly due to intense spasm in the internal anal sphincter muscle. Bleeding is the commonly associated symptom, especially when the fissure first develops. An anal lump may be noted. This may be a swollen skin tag associated with the fissure.

Medical treatment:

About 50 percent of anal fissures heal without the need for surgery. Many acute, superficial fissures heal spontaneously. Even deep chronic fissures can heal with conservative measures, dietary management (regular meals with increased fibre content), use of stool bulking agents (to soften your bowel motion) such as Mucilax, and frequent warm baths.

Often healing can be hastened by the application of a steroid ointment or suppositories, local anaesthetic ointment or a vaso-dilator paste.

Steroid ointment - use sparingly under medical supervision. It is not advised to use this form of treatment for prolonged periods of time.

Vaso-dilator paste - use under medical supervision. Use sparingly twice daily, morning and night. Increase the amount used to a little more each day. You may experience side-effects, headaches, rapid heart beat or faintness, if so then slightly decrease the amount to maximum benefit without any of the above side effects. Wash hands well after application of paste.

Suppositories - use under medical supervision. Insert twice daily after bowel motions. If the anal fissure is to heal with medical treatment, this should occur within a few weeks. Recurrence of the fissure months or years later may occur.

Surgical treatment:

Surgical treatment of an anal fissure can usually be performed as a day procedure in hospital. The usual operation is called a lateral internal anal sphincterotomy and is usually done under a general anaesthetic. The operation involves a small cut near the anal opening with the division of the lowest part of the anal sphincter muscle. The fissure itself may not be removed. The spasm is relieved and the fissure is then able to heal. Any large or troublesome skin tag related to the fissure is removed.

Post-operative care

Following lateral internal anal sphincterotomy constipation can be particularly unpleasant and painful so it is important to keep the bowel motions soft and regular.

Drink at least six to eight glasses of water a day. A high-fibre diet is recommended including plenty of cereal fibre, fresh fruit and vegetables. You may require a stool bulking agent such as Mucilax which will be prescribed by your surgeon.

Hygiene - it is important to keep the area clean and dry. Avoid using dry toilet paper, instead use a warm flannel or moist soft tissues. Saline baths (a cup of salt per bath) several times daily especially after bowel movements are good for hygiene and are very soothing.

Complications of surgery

These are very uncommon as the operation is simple and safe. Rarely, there may be postoperative bleeding. In approximately five percent of patients the healing of the wound may be delayed.

Anal sphincter function after surgery

The small incision in the internal anal sphincter (sphincterotomy) may result in a slight imperfection in the control of "wind" in the rectum. This is usually a temporary problem. Incontinence of faeces (loss of control of bowel movements) is an extremely rare complication.