Colorectal Neurovasculature and Anal Sphincter

The efficiency of any surgeon’s hand is dependent primarily on the knowledge that guides it. This article reviews the varied blood supply of the colon and rectum and notes that an important blood supply to the terminal ileum comes from the generally unknown ileal artery, which, when absent, creates a critical, poorly vascularized area inappropriate for an anastomosis. The external anal sphincters can be thought of as one continuous muscle divided by longitudinal bands into three parts; the internal sphincter is the end of the circular muscle of the rectum.