posterior collateral intercostal artery (anatomy)
Last reviewed 01/2018
Each posterior intercostal artery divides at the level of the angle of the superior rib within each interspace to give:
- a main branch which continues laterally within the subcostal groove of the superior rib
- a collateral intercostal branch which passes inferiorly to the superior margin of the inferior rib within each interspace
Alike the main branch, each collateral intercostal artery:
- runs in the plane between internal oblique and the innermost intercostals
- anastomoses with an anterior artery from either the internal thoracic or musculophrenic arteries