ABSTRACT
An anal fissure is defined as a distal, linear defect in the lining of the anal canal that extends from below the dentate line to the anal verge. It can be classified as primary or secondary, acute or chronic, and affects both adults and children. The accurate incidence of anal fissures is difficult to ascertain since many patients experience acute fissures but do not seek treatment, as the symptoms resolve within days. The persistence of the defect, thereby becoming a chronic fissure, is due to reasons that are not fully understood. Constipation has been recognised as the main causative factor in children with anal fissure. Direct trauma from a faecal bolus may cause damage to the anoderm. Fissures are defined as secondary when associated with other pathology. The most commonly associated conditions are Crohn’s disease, tuberculosis and HIV. They can also be post-interventional, such as non-healing haemorrhoidectomy wounds.
