Category - Anal
It is located in a position between the rectum and the anus, under the level of the pelvic diaphragm. It is situated in the anal triangle of the perineum, between the left and right ischioanal fossa. Author achudhan karunaharamoorthy reviewer dimitrios mytilinaios md, phd last reviewed june 15, 2020 the anal canal is the last part of the gastrointestinal tract. It is about 3 to 4 cm long and lies completely extraperitoneally. It begins at the anorectal junction distally from the perineal flexure and ends at the anus. The anal canal is the final segment of the gastrointestinal tract. It has an important role in defecation and maintaining faecal continence. In this article, we shall look at the anatomy of the anal canal its position, structure, relations and neurovascular supply. 1 it is the area between the anal verge and the junction of the stratified cuboidal and columnar epithelium (dentate line). 2 it is lined by squamous epithelium in the lower anal canal below which sebaceous glands and hair follicles arise but changes to stratified cuboidal and, finally, columnar epithelium of the rectum. anal canal, the terminal portion of the digestive tract, distinguished from the rectum because of the transition of its internal surface from a mucous membrane layer (endodermal) to one of skinlike tissue (ectodermal). The external anal sphincter muscle is the voluntary muscle that surrounds and adheres to the anus at the lower margin of the anal canal. This muscle is in a state of tonic contraction, but during defecation, it relaxes to allow the release of feces. The job of these ducts is to empty the secretions of anus glands into the lumen of the canal.