Intervertebral foramen

When the spinal vertebrae are articulated with each other the bodies form a strong pillar for the support of the head and trunk. Between every pair of vertebrae are two apertures (openings), the intervertebral foramina. The foramen allows for the passage of the spinal nerve root, dorsal root ganglion, the spinal artery of the segmental artery, communicating veins between the internal and external plexuses, recurrent meningeal (sinu-vertebral) nerves, and transforaminal ligaments.