Obturator artery

At a glance

English

Obturator artery

Latin (TA2)

Arteria obturatoria

System

Artery

Region

Trunk

Side

Paired, left and right

About the obturator artery

The obturator artery most often comes off the internal iliac artery's anterior trunk, though it may also come from the main stem, the superior gluteal artery or, now and then, the external iliac. It runs forwards and downwards on the side wall of the lesser pelvis towards the top of the obturator foramen, where it passes out through the obturator canal into the thigh.

Inside the pelvis it lies on the obturator fascia covering obturator internus, with the peritoneum and ureter on its medial side and the obturator nerve just above it. Here it gives iliac twigs to the iliac fossa that feed iliacus and the bone and join the iliolumbar artery, a vesical twig for the bladder and, last, a pubic branch that climbs on the back of the pubis to link with its fellow across the midline and with the inferior epigastric.

Once through the canal it forks into front and back branches, which run round the margin of the obturator foramen deep to obturator externus. The anterior branch curves down along the front edge of the foramen and supplies obturator externus, pectineus, the adductors and gracilis, joining the medial circumflex femoral artery. The posterior branch follows the back edge to the ischial ramus, feeds the hamstring and adductor fibres arising from the ischial tuberosity, and links with the inferior gluteal; from it comes the acetabular branch, which enters the hip through the acetabular notch and passes a small vessel to the femoral head within its ligament. In children this twig adds meaningfully to the blood of the femoral head; in adults it is too small to prevent bone necrosis after a femoral neck fracture.

In a sizeable minority of people the obturator artery, or a large accessory one, arises from the inferior epigastric artery and descends to the obturator foramen close to the femoral ring. When it runs along the edge of the lacunar ligament it lies right beside the neck of a femoral hernia and can be cut during repair, bleeding unseen into the pelvis; this arrangement is known as the corona mortis.

Course and supply

Arises from

Usually the internal iliac artery's anterior trunk; sometimes from its main stem, the superior gluteal, the external iliac or the inferior epigastric artery.

Ends in

Leaves the pelvis through the obturator canal and divides into anterior and posterior branches that encircle the obturator foramen.

Supplies

Supplies the pelvic side wall, iliacus and ilium, the bladder, the medial thigh muscles (obturator externus, pectineus, adductors, gracilis), the hamstring origins and the hip joint.