Operative procedures for fissure in ano.

Operative techniques commonly used for fissure in ano include: anal stretch, open lateral sphincterotomy, closed lateral sphincterotomy, posterior midline sphincterotomy and to a lesser extent dermal flap coverage of the fissure. Reports of direct comparisons between operative techniques for anal fissure are variable in their results. These reports are either subject to selection bias (in non-randomized studies) or observer bias (in all studies) or have inadequate numbers of patients enrolled to answer the question of efficacy.