Trunk vessels (aorta, vena cava, abdominal branches)
Posterior intercostal arteries
Arteriae intercostales posteriores (III-XI)
- Origin
- Nine paired branches arising directly from the posterior aspect of the thoracic aorta
- Insertion
- Course in the subcostal groove of ribs 3-11 within the intercostal neurovascular bundle, giving spinal branches (artery of Adamkiewicz) and anastomosing with anterior intercostals
- Function
- Supplies intercostal muscles, ribs, parietal pleura, chest wall skin, and spinal cord
- Innervation
- Sympathetic rami communicantes
- Movement & chain
- Arterial pulsatile flow
- Palpation
- Not palpated directly
- Clinical
- Artery of Adamkiewicz (arteria radicularis magna, usually from left 9th-12th intercostal) occlusion during thoracic aortic repair (TEVAR) can precipitate spinal cord infarction and paraplegia. Massive hemothorax from intercostal laceration.
- Segmental innervation
- T3-T11 spinal levels
- In clinical practice
- Chest tube insertion within the 'safe triangle' (5th intercostal space midaxillary line) strictly cranial to the lower rib; neuromonitoring post-aortic stent grafting
- Region in the model
- Trunk vessels (aorta, vena cava, abdominal branches)