Identification of factors affecting the outcome of transanal advancement flap repair for high transsphincteric fistulas

A fistula is defined as an abnormal communication between two epithelium lined surfaces. Perianal fistulas are abnormal communications between the anal canal and the perianal skin. Perianal fistulas have been treated since ancient times. Probably the first to describe the diagnosis and treatment of anal fistula was Sushruta around 600 BC. Around 430 BC, Hippocrates (460-370 BC) described perianal fistulas in more detail. It is remarkable that some of his guidelines carry worldwide popularity up to today. The estimated incidence of perianal fistulas varies between 0.86 and 2.32 per 10,000/year. There is a male predominance with a reported male-to-female-ratio varying from 2:1 to 5:1 2. The maximum incidence is between the third and fifth decades of life . Perianal fistulas account for a substantial discomfort and morbidity to the patient and although many fistulas are easily recognized and treated, others can be complex and difficult to treat.