Right subcostal vein

At a glance

English

Right subcostal vein

Latin (TA2)

Vena subcostalis dextra

System

Vein

Region

Trunk

Side

Single, on the midline

About the right subcostal vein

Below the right twelfth rib runs the right subcostal vein. It is the last vein in the line of segmental veins that accompany the ribs, and it lies under the final rib rather than in an intercostal space, which gives it its name.

Its territory is the strip of muscle and skin of the upper abdominal wall, at the back and side, just below the last rib. Small dorsal tributaries bring it blood from the back muscles and the vertebral region. It keeps company with the subcostal artery from the aorta and the subcostal nerve, the anterior ramus of the twelfth thoracic nerve, and the usual order applies: vein above, artery in the middle and nerve below.

Followed towards the spine, it passes behind the lateral arcuate ligament of the diaphragm and reaches the side of the twelfth thoracic vertebra. Here the right ascending lumbar vein meets it, and the two together give rise to the azygos vein. The azygos ascends on the right of the vertebral bodies, receives the right posterior intercostal veins, and arches forward to end in the superior vena cava.

As a root of the azygos vein, the right subcostal vein belongs to the channels that can carry blood from the lower half of the body to the superior vena cava if the inferior vena cava is blocked. It lies near the lower margin of the twelfth rib in a loin approach to the kidney or upper lumbar spine and may need to be controlled there.

Course and drainage

Begins at

Begins in the posterior and lateral abdominal wall just below the right twelfth rib.

Drains into

Unites with the right ascending lumbar vein beside the twelfth thoracic vertebra to form the azygos vein.

Drains

Drains the body wall immediately below the last rib on the right.