Rectal Arteries

Description

Arterial branches course along the sigmoid colon and continue inferiorly toward the rectum, mapping the vascular supply of the distal large bowel in an adult male. Proximally, sigmoid arteries from the inferior mesenteric artery run within the sigmoid mesocolon, forming arcades that send straight vasa recta to the bowel wall. More inferiorly, the superior rectal artery descends in the mesorectum and anastomoses with middle rectal branches from the internal iliac system and inferior rectal branches from the internal pudendal artery, creating clinically relevant convergence points around the distal gut tube. Small accompanying veins track the arterial paths, and perivascular lymph nodes align along the mesenteric pedicles. Attention to this territory matters because the rectum sits at a watershed between the inferior mesenteric and internal iliac circulations, so collateral pathways can determine perfusion after ligation, embolization, or atherosclerotic compromise. High ligation of the inferior mesenteric artery during anterior resection, or low tie preserving the left colic artery, changes the load on the marginal artery and the rectal anastomoses. Ischemic colitis at the rectosigmoid junction and anastomotic leak after low anterior resection both track back to these vascular patterns. Surgical atlases, colorectal oncology texts, and anatomy curricula covering hindgut derivatives can use this plate to teach named branches, arcades, and lymph node distribution along the sigmoid mesocolon and mesorectum. It also suits patient-facing education on hemorrhoidal disease and rectal bleeding when paired with endoscopic or angiographic correlation. Anatomical accuracy verified by SciePro's Medical Advisory Board.