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Basic anatomy

  • G. A. Santoro
  • G. Di Falco
  • C. Ratto

Abstract

The anal canal is 2–4 cm long. The dentate line of the mucosa denotes the squamocolumnar junction. The circular smooth muscle of the rectal wall continues downward as the internal anal sphincter (IAS). Anteriorly the muscle fibers from its anterior superior part run into the perineal body. The outer longitudinal component of the muscolaris propria extends as the longitudinal layer of the anal canal. It acts as an anchor, with its fibroelastic component permeating through the subcutaneous part of the external sphincter, terminating in the perianal skin.

Keywords

Anal Sphincter Anal Canal Rectal Wall External Anal Sphincter Internal Anal Sphincter 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Italia 2004

Authors and Affiliations

  • G. A. Santoro
  • G. Di Falco
  • C. Ratto

There are no affiliations available

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