Common iliac artery

The common iliac arteries are two large arteries that originate from the aortic bifurcation at the level of the fourth lumbar vertebra. They end in front of the sacroiliac joint, one on either side, and each bifurcates into the external and internal iliac arteries. They are about 4 cm long in adults and more than a centimeter in diameter. The arteries run inferolaterally, along the medial border of the psoas muscles to their bifurcation at the pelvic brim, in front of the sacroiliac joints.