Quick Facts
Origin: Common iliac vein.
Course: Vertical course, anterior to the transverse process of lumbar vertebra.
Tributaries: Lumbar veins.
Drainage: Posterolateral abdominal wall.
Origin
The ascending lumbar veins ascend from the common iliac veins in the pelvis, at approximately the level of the fifth lumbar vertebrae.
Course
From their origin, the paired ascending lumbar veins runs vertically, anterior to the transverse processes of the lumbar vertebrae. They connect ipsilateral lumbar veins, iliolumbar, and common iliac veins. The azygos vein arises from the union of the right ascending lumbar vein and the subcostal vein. The hemiazygos vein arises from the union of the left ascending lumbar vein and the subcostal vein. The ascending lumbar veins and the azygos veins connect the inferior vena cava and the superior vena cava.
Tributaries
The lumbar azygos vein usually enters the ascending lumbar vein. Additionally, it connects the lumbar veins from the ipsilateral side, but it can also connect the common iliac vein and iliolumbar vein. Blood flow in the lumbar veins can run in any direction.
Structures Drained
Through the lumbar veins, the ascending lumbar veins drain the posterior and lateral abdominal wall into the azygos vein on the right, and the hemiazygos vein on the left.
