Intercostal vein is a term that is used to describe the numerous veins that function to drain the rib cage's intercostals spaces. The intercostal spaces, often abbreviated as ICS, are located between two ribs. Rib cages consist of 11 of these spaces in total. Another common word for the intercostals spaces is "costae." A handful of different divisions of these veins exist. These divisions are posterior veins, anterior veins, superior veins, supreme veins, and subcostal veins. The posterior veins drain the spaces from the back. The anterior veins drain out of the anterior. The superior veins drain from the second, third, and fourth intercostals spaces. The supreme veins drain from the first costae. Lastly, the subcostal veins are situated directly under the bottom rib and are similar to the posterior veins. All of the intercostal vein divisions are named with the exception of the veins that are located between the spaces of ribs five and 11. The veins are in close proximity to the highest intercostals artery and the rami communicantes.
Written and medically reviewed by the Healthline Editorial Team
In Depth: Intercostal vein