Anal Fissure 

What is an Anal Fissure?

An anal fissure is a small tear in the lining (mucosa) of the lower third of the anal canal. Some fissures heal spontaneously whilst others become chronic forming an ulcer associated with anal sphincter spasm.

What causes an Anal Fissure?

Most anal fissures are caused by trauma.  Most commonly they occur after an episode of constipation.  They may also occur following childbirth, diarrhoea, etc...


The main symptoms are pain and occasionally blood when passing a bowel motion.  Occasionally a skin tag develops at the external end of the fissure.

Medical Treatment

Majority of anal fissures heal spontaneously. Conservative management includes:

  • Prevent constipation

    • Increase fluid and fibre intake

    • Stool softeners

    • Regular toileting and exercise

  • Salt water sitz baths

  • Topical application of muscle relaxing ointments

Surgical Treatment

Surgical treatment is undertaken when an adequate trial of medical management fails. Surgical management options will be discussed with your surgeon regarding the most suitable management. Surgical options include:


  • Botox injection:

    • relaxes the anal sphincter which subsequently aids in healing

    • 75% of fissures are resolved

    • Procedure may be repeated

  • Anal sphincterotomy:

    • involves making a small cut of some of the lower anal sphincter fibres, thus relieving sphincter spasm and assisting with healing the fissure.

    • 95% of fissures are resolved