OverviewThe muscles in the anal sphincter are used in the process of defecation.
Review Date 5/23/2016
Updated by: Jennifer Sobol, DO, urologist with the Michigan Institute of Urology, West Bloomfield, MI. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.