Sigmoid Arteries, Posterior View

Description

Arising as looping branches from the inferior mesenteric artery, the sigmoid arteries course within the sigmoid mesocolon toward the posterior surface of the sigmoid colon, then divide into ascending and descending limbs that interconnect along the mesenteric border. From this posterior perspective, the arterial arcades and their anastomoses are emphasized where they run medial to the haustrated bowel wall and adjacent to the rectosigmoid junction. Segmental landmarks of the large intestine are included for orientation, with the descending colon superior and left lateral to the sigmoid colon and the rectum continuing inferiorly in the midline. Appendices epiploicae punctuate the serosal contour. Posterior viewing matters because it mirrors the operative and endoscopic mental model for mesenteric-side vascular anatomy, where pedicles are identified, skeletonized, and divided close to their origin while preserving marginal flow. In sigmoid colectomy or low anterior resection, injury to the sigmoid arterial arcades or an underappreciated watershed at the rectosigmoid (Sudeck point) can contribute to ischemia and anastomotic leak, so the pattern of anastomoses and their proximity to the mesentery is not academic. Small-caliber branches are often labeled as arterioles in teaching, but in the mesocolon they function as named arterial branches with clinically relevant territories. Ideal for colorectal surgery teaching files, anatomy practicals on hindgut blood supply, and medical publishing content covering inferior mesenteric artery branching, marginal artery continuity, and safe ligation levels in the left colon. It also supports radiology education when correlating CT angiography or catheter angiography of the inferior mesenteric system with the expected arcades along the sigmoid. Anatomical accuracy verified by SciePro's Medical Advisory Board.