Anterior division of internal iliac artery

At a glance

English

Anterior division of internal iliac artery

Latin (TA2)

Divisio anterior arteriae iliacae internae

System

Artery

Region

Trunk

Side

Paired, left and right

About the anterior division of internal iliac artery

The internal iliac artery is a short vessel that drops into the pelvis from the bifurcation of the common iliac artery in front of the sacroiliac joint. Near the upper edge of the greater sciatic foramen it usually splits into a posterior division, which carries only parietal branches to the pelvic wall and buttock, and an anterior division, which runs forwards and downwards along the side wall of the pelvis towards the ischial spine.

The anterior division gives two kinds of branch. Its visceral branches reach the bladder and rectum: the umbilical artery, whose open first part sends superior vesical arteries to the upper bladder before the rest closes off as the medial umbilical ligament, and the middle rectal artery. Its parietal branches leave the pelvis: the obturator artery runs forward on the side wall to the obturator canal and the medial compartment of the thigh, while the inferior gluteal and internal pudendal arteries usually end the division by passing out through the greater sciatic foramen below piriformis.

The pattern of branching is among the most variable in the body. Branches may arise singly, in common trunks, or from the posterior division instead, so surgeons identify each vessel by where it goes rather than by the order it leaves the parent.

Because so much pelvic blood passes through it, the division matters in pelvic fracture and pelvic surgery. Bleeding from its branches can be controlled by radiological embolisation or by ligating the internal iliac artery, and the rich anastomoses across the midline and with lumbar and sacral vessels keep the pelvis perfused afterwards.

Course and supply

Arises from

The internal iliac artery, which divides into anterior and posterior divisions near the upper border of the greater sciatic foramen.

Ends in

Ends in its terminal branches, usually the inferior gluteal and internal pudendal arteries, after giving off its visceral and obturator branches.

Supplies

Supplies the bladder, the lower rectum, the perineum, the gluteal muscles below piriformis and, through the obturator artery, the adductor compartment of the thigh.