Fissures that are off midline require further investigation. Ninety percent of fissures are located in the anterior or posterior midline. Fissures that are not midline may be associated with ...

A majority of anal fissures occur at the posterior midline. In males, about 1% of all fissures occur at the anterior midline, whereas in females the incidence is approximately 10%. 1 In rare ...

An anal fissure is a tear in the squamous epithelium that lines the anal canal. Most fissures (90%) occur in the posterior midline and the remaining 10% occur in the anterior midline.