Corpus: External vertebral venous plexus
1. Definition
The external vertebral venous plexus is a network of veins that surrounds the front and back of the vertebral bodies or vertebral arches. It drains venous blood from the vertebrae and the surrounding ligamentous structures.
2. Anatomy
The external vertebral venous plexus is divided based on its location:
- Anterior external vertebral venous plexus
- Posterior external vertebral venous plexus
The anterior plexus lies in front of the vertebral body, while the posterior plexus forms a venous network over the vertebral arches and transverse and spinous processes. It communicates with the internal vertebral venous plexus through anastomoses, including the basivertebral veins.
At the base of the skull, the external vertebral venous plexus receives blood from the condylar emissary vein.
The vertebral venous plexuses create a longitudinal venous pathway that runs parallel to the superior and inferior vena cava. Along with the azygos and hemiazygos veins, they form a venous collateral circulation system.