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The anus is a sphincter at the end of the rectum through which passes stool during defecation. The anal sphincter is a critical mechanism for control of fecal continence.
Review Date 6/11/2024
Updated by: Jenifer K. Lehrer, MD, Department of Gastroenterology, Aria - Jefferson Health Torresdale, Jefferson Digestive Diseases Network, Philadelphia, PA. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.