Anal fissure is one of the most frequent anal conditions. Sphincter hypertonia engendering local ischemia is considered as the main causal mechanism. Medical management is to be offered as a primary approach, with treatment of constipation being a mainstay of conservative therapy. However, when symptoms persist after 4 to 8 weeks of appropriate medical treatment, surgery should be considered. The lateral internal sphincterotomy remains the technique of choice for many practitioners, which is supported by good empirical evidence and by recommendations of scientific societies. It reduces the hypertonia by decreasing the pressure in the anal canal, thereby improving local vascularization and allowing the fissure to resolve.Common causes of anal fissure include :