Subcostal arteries

Subcostal arteries are the final pair of arteries branching from the thoracic aorta. They are located below the last rib, hence the name 'subcostal'. The term 'subcostal' is derived from the Latin words 'sub' meaning 'under' and 'costa' meaning 'rib'.

Anatomy

The subcostal arteries are the lowest pair of twelve pairs of thoracic arteries that supply the thorax, abdomen, and back. They are similar to the intercostal arteries, but are located below the twelfth rib. Each subcostal artery runs along the lower border of the twelfth rib behind the kidney and in front of the quadratus lumborum muscle.

Branches

The subcostal arteries give off several branches, including the lateral cutaneous branch, muscular branches, and a spinal branch. The lateral cutaneous branch supplies the skin and muscles of the back, while the muscular branches supply the quadratus lumborum muscle. The spinal branch enters the vertebral canal through the intervertebral foramen to supply the spinal cord and its membranes.

Clinical significance

Damage to the subcostal arteries can lead to significant blood loss due to their large size and the lack of collateral circulation. This can occur due to trauma or during surgical procedures involving the lower thorax or upper abdomen.

See also

• Thoracic aorta
• Intercostal arteries
• Quadratus lumborum muscle