At which spinal segment do the iliac arteries bifurcate?

The iliac arteries are the major arteries that supply blood to the pelvis and lower limbs. They bifurcate into the right and left common iliac arteries from the abdominal aorta. The common iliac arteries further divide into the internal and external iliac arteries.

The bifurcation of the aorta into the common iliac arteries typically occurs around the level of the L4 vertebra. The iliac arteries themselves will continue to run along the L5-S1 intervertebral space, where the common iliac arteries begin to branch into the internal and external iliac arteries. Therefore, stating that the iliac arteries bifurcate at the L5-S1 level aligns with anatomical understanding, as this is a critical area of transition for the blood supply to the lower body.

This anatomy is important not only for understanding vascular supply but also for various medical and surgical procedures involving the lower abdomen and pelvis, such as vascular procedures, surgeries, or even in assessing conditions like aneurysms or vascular malformations.