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MattiV.Kairaluoma

Anal Fissure

An anal fissure is a sore ulcer on the external orifice of the anus.
Conservative treatment should be preferred in newly emerged and mild cases.
Prolonged conditions are treated in specialized care with botulinum or surgery.
Remember inflammatory bowel diseases Ulcerative Colitis Crohn's Disease and cancer Colorectal Cancer in the differential diagnosis.

The aetiology of an anal fissure is not exactly known but it most obviously originates from a small injury on the mucosa of the rectal channel, which results in spastic contractions of the internal anal sphincter. Since the blood vessels to the mucosa run through the sphincter muscle, the mucosal circulation is impaired by the spasm.
The most common location of the fissure is in the posterior midline, where the circulation of the rectal mucosa is the weakest even in the normal state.
Hard stools in association with constipation or frequent bowel movements in association with a diarrhoeal disease may act as predisposing factors.

The main symptom is anal pain that intensifies during defecation.
Small amounts of bright blood may be seen in the toilet paper.
A fissure is usually located dorsally in the midline of the anal canal (> 80%) (picture 1). The second most common site is the anterior midline (> 10%).
Suspect Crohn's disease Crohn's Disease if a fissure is not located in the midline.
If the fissure has an abnormal appearance, malignancy should be suspected.

Spontaneous recovery occurs in 60-80%.
If the symptoms have not been present for longer than a month, spontaneous recovery should be expected. Local anaesthetic gel or ointment before and after defecation may alleviate pain. Toilet hygiene should be good. Warm sitz baths (40°C) twice daily for 15-20 min may relax sphincter spasm and alleviate pain.
Ointment treatment can also be started immediately if the symptoms are severe.
Topical extemporaneous preparations
- Diltiazem.hydrochlorid. 20 mg; emollient (oil in water emulsion) 980 mg: 2 cm of ointment rubbed gently on the external orifice of and into the anus twice a day for 6 weeks
- Nifedipine 60 mg; macrogol 400 135 mg; emollient (oil in water emulsion) ad 30 g: ointment applied 3 times a day for 8 weeks
- Unlike nitrate ointment, these preparations do not cause headache.
Nitrate ointment put daily into the anal passage has been shown to be significantly better than placebo and may help to avoid surgery in a number of patients Glyceryl Trinitrate in the Treatment of Anal Fissure. A ready-made preparation is available (Rectogesic^® ).
- Expensive and causes often headache.
If, during conservative treatment, the pain on the anus worsens or becomes continuous, it may be caused by an abscess that has developed between the sphincter muscles Anal Abscess and Anal Fistula. Its treatment is an emergency incision.
Obstipation Obstipation in the Adult should be managed with bulk laxatives.

If a fissure persists for more than 2 months the condition should be classified chronic. The fibres of the internal sphincter muscle are visible at the bottom of the fissure. A sentinel haemorrhoid is often seen in the anus, and there is a hypertrophied anal papilla at the dentate line in the anal canal.
Conservative treatment with nitrate ointment or calcium channel blocker cream should be tried as 50% heal with this therapy. Botulin toxin injections have also been successful. It is perhaps slightly better treatment than ointments but considerably more expensive 1.
In surgical therapy, internal sphincterectomy is performed under local or general anaesthesia Operative Procedures for Fissure in Ano. Manual anal sphincter dilatation is no longer recommended Operative Procedures for Fissure in Ano. Internal sphincterectomy in local anaesthesia can be performed in ambulatory care. The fissure itself does not need to be treated.
If the fissure recurs after sphincterotomy, a skin flap can be transplanted from outside the anus on the ulcer (anoplasty).
A disturbingly large sentinel fold and hypertrophic anal papilla can be excised.

Nelson RL, Thomas K, Morgan J, et al. Non surgical therapy for anal fissure. Cochrane Database Syst Rev 2012;2012(2):CD003431 [PubMed]