Subcostal Artery

arteria subcostalis

The subcostal artery is the last pair of segmental arteries from the descending thoracic aorta, running along the inferior border of rib 12 (below the last rib, hence 'subcostal'). It supplies the abdominal wall musculature of the flank and accompanies the subcostal nerve (T12) along the inferior border of the 12th rib. It anastomoses with the superior and inferior epigastric arteries and with the iliolumbar artery.

Region: Abdomen

Clinical Relevance

Clinical Notes

The subcostal artery and nerve are the key neurovascular structures at risk during subcostal (Kocher) incision approaches to the right upper quadrant and retroperitoneum. Damage to the subcostal neurovascular bundle produces a sensory deficit and muscle weakness along the lower flank and upper abdominal wall. The subcostal artery also provides blood supply to the lower chest wall and must be considered in planning flaps based on the lower intercostal angiosome. In nephrectomy through the retroperitoneal approach, the subcostal neurovascular bundle is identified and retracted before the kidney is mobilised.

Pathology

Common Injuries & Conditions

Subcostal Nerve and Artery Injury in Flank Approach

Retroperitoneal flank approaches to the kidney and adrenal gland risk the subcostal neurovascular bundle running along the inferior border of the 12th rib; injury produces a painful lower flank hernia (from paralysis of the external oblique, internal oblique, and transversus abdominis) and sensory loss in the subcostal dermatome.