The spinal veins (veins of the medulla spinalis or veins of the spinal cord) are situated in the

pia mater Pia mater ( or ),Entry "pia mater"
in
venous plexus In vertebrates, a venous plexus is a normal congregation anywhere in the body of multiple veins. A list of venous plexuses: * Basilar plexus * Batson venous plexus * Internal vertebral venous plexuses * Pterygoid plexus * Submucosal venous ple ...

. They emerge chiefly from the median fissures of the

medulla spinalis The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone). The backbone encloses the central canal of the spinal ...

and are largest in the

lumbar region In tetrapod anatomy, lumbar is an adjective that means ''of or pertaining to the abdominal segment of the torso, between the diaphragm and the sacrum.'' The lumbar region is sometimes referred to as the lower spine, or as an area of the back i ...

. In this plexus there are: * (1) two ''median longitudinal veins'', one in front of the anterior fissure, and the other behind the

posterior sulcus Posterior may refer to: * Posterior (anatomy), the end of an organism opposite to its head ** Buttocks, as a euphemism * Posterior horn (disambiguation) * Posterior probability The posterior probability is a type of conditional probability that r ...

of the cord. * (2) four ''lateral longitudinal veins'' which run behind the nerve roots. They end in the

intervertebral veins The intervertebral veins accompany the spinal nerves through the intervertebral foramina; they receive the veins from the medulla spinalis, drain the internal and external vertebral plexuses. Their drainage depends upon the part of the body: * N ...

. Near the base of the skull they unite, and form two or three small trunks, which communicate with the

vertebral veins The vertebral vein is formed in the suboccipital triangle, from numerous small tributaries which spring from the internal vertebral venous plexuses and issue from the vertebral canal above the posterior arch of the atlas. They unite with small ve ...

, and then end in the

inferior cerebellar veins The cerebellar veins are veins which drain the cerebellum. They consist of the superior cerebellar veins and the inferior cerebellar veins (dorsal cerebellar veins). The superior cerebellar veins drain to the straight sinus and the internal cere ...

, or in the

inferior petrosal sinuses The inferior petrosal sinuses are two small sinuses situated on the inferior border of the petrous part of the temporal bone, one on each side. Each inferior petrosal sinus drains the cavernous sinus into the internal jugular vein. Structure The ...

References

External links

Veins of the torso {{circulatory-stub