Anatomy, Physiology, and Measurement of Physiologic Function for Colorectal Surgery

Solid surgical decision making and operative planning are the cornerstones of excellence in outcomes and performance. Beyond the knowledge of the pathologic process, they require an in-depth understanding of the anatomy and physiology of the area impacted by disease or dysfunction. The embryology and anatomy, as well as the physiology of the appendix, colon, rectum, and anus, are reviewed here, with a particular focus on their impact on surgical evaluation and decision making. Tables outline artery-dependent embryologic development of the gastrointestinal system, embryologic development and related malformations, principles and critical structures during colorectal mobilization/resection, clinical impact of anatomic differences between colon and rectum, mediators and drugs affecting colonic motility, pelvic floor muscles, and anophysiology testing. Figures depict malrotation, colon walls, computed tomographic colonography, coronal and lateral views of the rectum, rectal cancer, vascular anatomy, colonic wall innervation, diurnal variation of colonic motility, assessment of colonic transit by means of a Sitzmark study, pelvic organ prolapse, and electrolyte transport mechanisms with