The common iliac artery. The right and left arteries are two end branches into which the aorta devides at the level of fourth lumbar vertebrae. The division occurs slightly to the left of midline, as a result of which the right common iliac artery is 6-7 cm longer than the left artery. From the bifurcation at the level of sacroiliac joint its divide into the external and internal iliac arteries.
The internal iliac artery. Arising from the distal end of the common iliac artery at the level of the sacroiliac joint, descends into the true pelvis and extends to the superior edges of the greater sciatic foramen. Its division into the posterior trunk: aa.ililumbalis, sacralis lateralis and glutea superior; and anterior trunk: remaining of the internal iliac artery. There are parietal (iliolumbar artery, lateral sacral, superior gluteal, obturator and inferior gluteal) and visceral (umbilical artery, ureteric branches, superior and inferior visceral arteries, uterine artery and middle rectal artery) branches.
The external iliac artery. Beginning at the level of sacroiliac joint, stretches down and forward along the medial edge of m. psoas to the inguinal ligament. Branches: 1) The inferior epigastric artery passes medially and then upward between the fascia transversalis in front and peritoneum parietale in back, and enters the sheath of the rectus abdominalis muscle. 2) The deep circumflex iliac artery bending around the iliac bone passes parallel to the inguinal ligament toward the iliac crest posteriorly, supplying m. transversus and iliac muscle with blood.