Second posterior intercostal artery
Arteria intercostalis posterior secunda
The artery of the second intercostal space, the lower of the two vessels supplied by the supreme intercostal artery.
At a glance
- English
- Second posterior intercostal artery
- Latin (TA2)
- Arteria intercostalis posterior secunda
- System
- Artery
- Region
- Trunk
- Side
- Paired, left and right
About the second posterior intercostal artery
The posterior intercostal arteries are paired vessels that run around the chest wall in the spaces between the ribs. From the third space downwards they come directly from the descending aorta. The second, like the first, comes from the supreme intercostal artery, the descending branch of the costocervical trunk of the subclavian artery.
After crossing the neck of the first rib, the supreme intercostal artery continues down in front of the neck of the second rib and gives the second posterior intercostal artery into the space below. It may then send a small branch further down to join the third posterior intercostal artery, which links the subclavian and aortic supplies of the chest wall.
In the space the artery travels with the posterior intercostal vein and the second intercostal nerve. Near the angle of the rib the three structures move into the costal groove under the lower border of the rib above, with the vein highest, the artery in the middle and the nerve lowest. The artery supplies the intercostal muscles, the parietal pleura and the overlying skin, gives a dorsal branch to the back and a spinal branch, and ends in front by meeting an anterior intercostal branch of the internal thoracic artery.
The position of the vessels high in the space explains why needles and drains are passed into the chest just above the upper border of a rib. The vein of the second space usually joins the superior intercostal vein rather than draining directly to the azygos or hemiazygos system.
Course and supply
- Arises from
- The supreme intercostal artery, branch of the costocervical trunk, as it descends over the neck of the second rib.
- Ends in
- Runs forwards in the second intercostal space and anastomoses with the anterior intercostal branch of the internal thoracic artery.
- Supplies
- Supplies the muscles, pleura and skin of the second intercostal space, with dorsal and spinal branches.
Anthromica
See the second posterior intercostal artery where it really sits, with every layer of the body around it.
- Every layer, one body. Peel from muscle to bone, nerve, vessel and organ, and turn it any way.
- English and Latin. Every structure named the way your exam names it.
- Quiz until it sticks. Short drills on the structures you keep missing.
Free to start. No card.
