Intercostal nerves and arteries

Question 1

Where are the intercostal n, a, v found in the thorax?

Answer 1

Between the ribs in the costal groove.
Nerve is the most inferior.
Lies between the innermost and internal intercostal muscle.

Question 2

What do the intercostal nerves supply?

Answer 2

Innervate the external, internal and innermost intercostal muscles and the skin overlying the same space.
Branches to the pleura
The lower 6 nerves give branches to the peritoneum and supply the muscles of the abdominal wall

Question 3

What are the branches of the typical thoracic spinal nerve?

Answer 3

1) lateral 2) anterior cutaneous branches to the skin over that intercostal space
3) collateral branches to intercostal muscle
4) unnamed branches to intercostal muscle
5) pleural and peritoneal branches (lower 6 intercostal nerves)
6) articular branches to joints of the rib

Question 4

Where do the posterior intercostal arteries arise from?

Answer 4

The upper 9 posterior intercostal arteries arise from the thoracic aorta. The lower 2 posterior intercostal arteries arise from the costocervical trunk (branch of the subclavian a)

Question 5

Where do the anterior intercostal arteries arise from?

Answer 5

The upper 6 anterior arteries are branches of the internal thoracic artery (branch of subclavian artery).
The lower 5 anterior intercostal arteries are branches of the musculophrenic artery (branch if the internal thoracic)

Question 6

What do the intercostal arteries supply?

Answer 6

Posterior intercostal a. supply posterior part of that intercostal space
Anterior intercostal a. supply the anterior part of that intercostal space