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Anal sphincter anatomy

Anal sphincter anatomy

Overview

The muscles in the anal sphincter are used in the process of defecation.

Review Date 10/31/2022

Updated by: Michael M. Phillips, MD, Emeritus Professor of Medicine, The George Washington University School of Medicine, Washington, DC. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.