The anastomosis of the colic arteries around the concave margin of the large intestine forms a single arterial trunk, known as the marginal artery. It begins at the ileocecal junction, where it anastomoses with the ileal branches of the superior mesenteric artery and ends where it anastomoses with the superior rectal artery.
Importance of marginal artery:
Marginal artery is of significant clinical importance because it forms an important anastomosis between the superior mesenteric artery and the inferior mesenteric artery. It is sufficiently large to supply the oxygenated blood those parts of large intestine which are supplied by the inferior mesenteric artery. For this reason, the inferior mesenteric artery doesn’t have to be re-implanted into the repaired abdominal aorta in abdominal aortic aneurysm repair.