Abdominal aorta and its branches

 Overview of the abdominal aorta

The abdominal aorta is a continuation of the descending thoracic aorta.

It supplies all of the abdominal organs, and its terminal branches go on to supply the pelvis and lower limbs. It also supplies the undersurface of the diaphragm and parts of the abdominal wall

Anatomical relationships

Running parallel to the aorta on its right-hand side is the inferior vena cava, the cisterna chyli, the beginning of the azygos vein, and the para-aortic lymph nodes.

Running on its left-hand side is the left sympathetic trunk and the para-aortic lymph nodes.

Organs situated directly in front of the aorta include the stomach, duodenum and pancreas.

It is also crossed anteriorly by

Branches of the abdominal aorta

Three single anterior visceral branches (coeliac, superior mesenteric artery, inferior mesenteric artery)

Three paired lateral visceral branches (suprarenal, renal, gonadal)

Five paired lateral abdominal wall branches (inferior phrenic and four lumbar)

Three terminal branches (two common iliac arteries and the median sacral artery)

For some reason, there are three suprarenal arteries. These supply the adrenal glands. The superior branch is derived from the inferior phrenic artery, the middle branch originates directly from the aorta, and the inferior branch comes off the renal artery.

The IVC runs parallel to the aorta on its right-hand side.

Because the IVC is in the way, the right renal artery has to pass behind it to get to the right kidney.

The gonadal arteries (testicular in men, ovarian in women) are situated surprisingly high up in the abdomen. This is because, during early fetal life, the gonads begin to develop up next to the kidneys before migrating downwards to their proper positions. They get their blood supply from where they started, not from where they end up.

The lumbar arteries arise posteriorly and will not be easily visible on most anatomical prosections.

The fifth lumbar arteries on either side arise from the median sacral artery.