Subcutaneous Lateral Sphincterotomy: An office treatment

Sphincterotomy is a way of treating anal fissures with minimal pain. The procedure can often be carried out in the office with only Local Anaesthetic infiltration thus avoiding hospitalisation and a General Anaesthetic. The surgery itself only takes a few minutes. It consists of making a small cut in the skin near the anal canal and grasping what is termed “the internal sphincter” and dividing it. This sphincter often in spasm when a patient has an anal fissure and dividing the sphincter relieves this spasm.

Development of an anal fissure

Following constipation or a change in bowel habits, a tear can occur in the lining of the anal canal. As a result of this tear, patients experience pain, burning and some slight blood loss with their bowel action. This condition may become chronic as repeated tearing occurs and the underlying muscle goes into spasm.

The applications proprietary are applying creams or ointments such as Rectinol or prescription medication such as Proctosedyl have a Local Anaesthetic agent and Cortisone which decreased the pain, swelling and sensitivity. More recently there have been two new additions non-surgical ways of treating a fissure. These are the tablet Rectogesic and Botox. Both were developed originally for other purposes.

Rectogesic consists of an agent, which dilates the blood vessels promotes the blood supply to the area and thus theoretically helps the fissure to heal. The basic component was originally used for people who had angina due to blocked arteries in the heart. The idea being that these would help dilate the arteries and promote the blood flow.

One of the side effects of Rectogesic, which needs to be taken for two or three weeks, is a headache, which may occur and often stops patients taking it. The other newer agent is Botox, which is used in cosmetic surgery to relax muscle sphincters. It is important in diagnosing an anal fissure that the examining doctor takes this into account because routine rectal examination can be extremely painful.

The first clue that a doctor would have that you have an anal fissure is the history you give of severe pain with a bowel action and a drop of blood. When you are examined, when the buttocks are parted with a bad fissure this will cause pain. It may be also a sentinel pile as mentioned. Often the fissure can actually be seen as the buttocks are parted. However there may be so much pain and spasm that the fissure cannot be visualised. An attempt at rectal examination then would be extremely painful. Thus a full examination with a fissure at that time is not always possible.

Thus some patients are treated a little blind at first and then re-examined later. However it is important at that first visit to differentiate your pain from that of a small abscess, which can also be very painful. With an abscess there is usually some swelling – and a painful lump.

Some chronic fissures are not quite as painful and when a rectal examination is done with a glove the rough fissure can be palpated confirming the diagnosis. At that time a sigmoidoscopy may be carried out to ascertain that there are no other problems. Fissures are sometimes found in association with haemorrhoids. It would be inadvisable to have haemorrhoids rubber band ligated whilst the fissure is still active.

A certain number of patients with an anal fissure do come to need surgery. This surgery is called a subcutaneous lateral sphincterotomy. Years ago the recommended treatments for a fissure were dilatation of the anus under an anaesthetic. This broke down the sphincters. However, this was found to cause some leakage of faeces – incontinence, after the procedure in a small number of patients and has been virtually abandoned as a way of treatment.

With subcutaneous lateral sphincterotomy there is a theoretical risk that the same problem could occur. However in the experience of most Surgeons who specialise in this area the incidence of this is extremely low. However patients who have other conditions or who are very elderly, consideration needs to be given to this before the operation is carried out. It should also be discussed with the patient by the doctor prior to the procedure being carried out.

Sphincterotomy procedure

The patient is asked to lie on their side facing the wall. Local Anaesthetic is then administered with a fine needle and the area rapidly becomes anaesthetised. Following the injection there is no pain felt during the procedure. A small cut is made in the loose skin adjacent to the back passage. The muscle – sphincter that is in spasm is identified, grasped and divided. No suturing is required and the wound heals spontaneously. A dressing pack is inserted and this is removed the following day. A small pad may need to be worn for a few days.

After care

Bowels can be used as desired. The first bowel action is usually less painful. The skin wound usually heals within a few days. The fissure may take a week or two to heal and sometimes does not heal for a long time. Pain however is relieved because the spasm is gone. Sometimes associated with the fissure are the skin tags, which may be removed. A skin tag may be on the outside and there may also be a little polyp at the base of the fissure internally. The edges of the fissure may be trimmed to help it heal up.

The skin is then kept dry and a powder may be used. Bruising of the area is of no consequence and resolves rapidly. If necessary, mild painkillers may be taken but in many instances these are not required. Heavy constipating tablets should be avoided if possible. The amount of time off varies and the rate of healing and absence of pain caries.

As for all surgery the result cannot be guaranteed. There are a small number of patients where the surgery appears to be ineffective and a procedure may be required. Other possible risks are that even after successful surgery a fissure occurs from time to time at a later date. There are occasional complications with the wound of the operation such as some bleeding underneath the wound or infection.

Some anal fissures can be a very painful problem for patients and it is frustrating, as it is only just a small thing but still disabling and irritating. Treatment varies from just altering bowel habits and use of local applications to the use of surgery. The patient will usually indicate when they want surgery because of their exasperation with the pain or chronicity of the problem. This needs to be discussed in full with the treating doctor.