Anorectal Physiology

  • Richard E. Karulf


Normal bowel continence and evacuation are complex ­processes that involve the coordinated interaction between multiple different neuronal pathways and the pelvic and perineal musculature.1 The importance of the anatomic relationships of the pelvic floor in maintaining normal continence has been suggested since the 1950s.2 However, the complex series of neural and behavioral-mediated interactions, combined with a lack of an ideal study to take all elements into account, makes complete understanding of anorectal anatomy and physiology’s role in preserving continence difficult.3 Complicating this are multiple other factors that play a role in normal regulation such as systemic disease, sphincter integrity, bowel motility, stool consistency, evacuation efficiency, pelvic floor stability, cognitive and emotional affects.4



This chapter was written by Susan M. Parker and John M. Coller in the first edition of this textbook.


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Copyright information

© ASCRS (American Society of Colon and Rectal Surgeons) 2011

Authors and Affiliations

  • Richard E. Karulf
    • 1
  1. 1.Division of Colon and Rectal Surgery, Department of SurgeryUniversity of MinnesotaEdinaUSA

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