marginalarterier

Marginalarterier, or marginal arteries, is a term used in anatomy to describe arteries that run along the margin or border of an organ and form a collateral arterial network. The best described example is the marginal artery of the colon (arteria marginalis coli), often called Drummond's marginal artery. It is formed by the anastomoses of terminal branches from the major colic arteries: from the superior mesenteric artery (ileocolic, right colic, and middle colic) and from the inferior mesenteric artery (left colic and sigmoid arteries). The artery courses along the mesenteric (inner) border of the colon, from the ileocecal junction to the rectosigmoid junction, and runs close to the teniae coli.

Function and significance: The marginal artery provides collateral perfusion to the colon, ensuring continuity of blood supply to segments if one principal artery is obstructed or narrowed. This redundancy is particularly important during dynamic changes in blood flow or when partial resections are performed.

Variations and clinical relevance: The completeness of the marginal artery is variable among individuals. In some people, portions of the marginal arcade are incomplete or absent, especially at the splenic flexure and the rectosigmoid junction. These areas are considered watershed zones and are more susceptible to ischemia during systemic hypotension, atherosclerosis, or occlusive disease. In colorectal surgery, knowledge of the marginal artery’s presence and robustness helps plan resections and anastomoses to preserve bowel viability and reduce the risk of ischemic complications.