Common iliac arteries are two large terminal branches of abdominal aorta. They arise from the bifurcation of aorta at the level of 4th lumbar vertebra.
Both right and left common iliac arteries, in adults, are about 4cm long and more than 1cm in diameter.
Right and left common iliac arteries arise from the terminal part of abdominal aorta at the level of 4th lumbar vertebra.
After their origin, the arteries (on their respective side) run downward and laterally along the medial border of psoas muscle.
Each artery ends in front of the sacroiliac joint of respective side. Each artery bifurcates into external and internal iliac arteries.
At the bifurcation into external and internal iliac arteries, the common iliac artery is crossed in front by the ureter. This relation is fairly constant.