Posterior intercostal arteries at a glance
- What it is
- Paired arteries running in the intercostal spaces along the lower border of each rib.
- Location
- The first two come from the supreme intercostal artery; the lower nine arise from the thoracic aorta and run between internal and innermost intercostal muscles, giving dorsal and collateral branches.
- Function
- They supply the intercostal muscles, ribs, skin, breast and spinal canal contents.
- Body system
- Cardiovascular · single, midline structure
- FMA ID
- FMA63822 (Foundational Model of Anatomy)
Key facts
- They anastomose with the anterior intercostal arteries.
- The right posterior intercostal arteries are longer than the left, because the aorta lies to the left of the midline; they cross behind the oesophagus, azygos vein and thoracic duct.
Clinical relevance
Aortic coarctation can enlarge them, causing rib notching.
Structures next to the posterior intercostal arteries
The nearest named structures in the 3D model, measured from the centre of each part:
- Internal intercostal muscle · muscular
- Anterior intercostal veins · cardiovascular
- External intercostal muscle · muscular
- Azygos vein · cardiovascular
- Caudate lobe of liver · digestive
- Posterior leaflet of tricuspid valve · cardiovascular
- Intervertebral disk of ninth thoracic vertebra · skeletal
- Coronary sinus · cardiovascular
- Posterior interventricular branch of coronary artery · cardiovascular
- Hepatic vein · cardiovascular
References
- Foundational Model of Anatomy: Posterior intercostal arteries (FMA63822). EMBL-EBI Ontology Lookup Service.
- OpenStax. Anatomy and Physiology 2e, §20.1 Structure and Function of Blood Vessels. Rice University, 2022.
- Mitsuhashi N. et al. (2009). BodyParts3D: 3D structure database for anatomical concepts. Nucleic Acids Research 37, D782–D785. Data © The Database Center for Life Science, CC BY 4.0.
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