Thorax Lab 1 Module 2

SECTRA TABLE WORK: Page 5 of 5

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Let's examine the vascular supply:

Rotate and remove the left thorax and the sternum to expose the right thorax.

You will now add the components of the intercostal vascular and nerve supply.

	Add the intercostal arteries and observe their connection to the descending thoracic aorta.
	Add the azygos vein, the hemiazygos vein, the accessory hemiazygos vein,the right superior intercostal vein and the posterior intercostal veins. Note that all of these veins ultimately drain into the azygos system, which empties into the superior vena cava (SVC).
	Add the intercostal nerves.

	Notice that thoracic nerve 1 sits on top of the first rib. To what nerve grouping does it contribute?
Thoracic nerve 1 (T1) contributes to the brachial plexus.

	Observe that each intercostal neurovascular bundle (vein, artery, and nerve) travels in the costal groove along the inferior border of the rib. Why is this clinically significant?
The neurovascular bundle is vulnerable to injury during procedures such as thoracentesis or chest tube insertion. To avoid damage to these structures, clinicians are taught to insert instruments just above the superior border of the inferior rib.

Add the internal thoracic artery and vein, which run posterior (deep) to the costal cartilages and parallel to the sternum.

	From which artery does the internal thoracic artery arise? Where does the internal thoracic vein drain?
The internal thoracic artery arises from the subclavian artery. The internal thoracic vein drains into the brachiocephalic vein.

Re-add the sternum and costal cartilages..

Rotate the chest to observe the anterior-to-posterior relationships of the thoracic wall structures.