3D Models Related Images

Anterior View of Medulla and Proximal Cervical Spinal Cord

Surgical Correlation


Anterior view of medulla and proximal cervical spinal cord. Anterior portions of the atlas and axis as well as the basilar portion of the occipital bone (clivus region) have been removed to expose the proximal cervical spinal cord and the medulla. Along the anterior surface of the spinal cord, within the anterior median fissure, is the anterior spinal artery. Anterior spinal arteries arise from the vertebral arteries and then anastomose into a single vessel at the level of the foramen magnum. This artery is reinforced by other branches distally that enter the spinal canal through intervertebral foramina. The artery spinal artery supplies the anterior two-thirds of the spinal cord. Paired posterior spinal arteries (not visible here) supply the posterior one-third. The anterior spinal vein accompanies the artery. The posterior inferior cerebellar arteries, the largest branches of the vertebral arteries, travel posteriorly and lateral to the medulla near the roots of the glossopharyngeal (CNIX) and vagus (CNX) nerves and supply the caudal part of the cerebellum. Rostral to these nerves, the facial (CNVII) and vestibulocochlear (CNVIII) nerve complex can be seen emerging from the lateral pontomedullary junction. Arising from the anterolateral surface of the cord are anterior rootlets and roots of cervical spinal nerves. The spinal portion of the spinal accessory nerve can be seen as a single trunk that ascends through the foramen magnum to unite with its cranial portion, which arises from the medulla. The spinal portion arises from fibers from ventral horn cells between C1 and C5 segments. These fibers emerge from the cord between the anterior and posterior spinal nerve roots before joining to form a single trunk. Also, the denticulate ligaments, seen here as glistening white structures along the lateral border of the cord, are likewise positioned between anterior and posterior nerve roots. These are longitudinal condensations of pia mater that attach as focal adhesions to the spinal dura to stabilize the spinal cord within the dural sac. (Image courtesy of AL Rhoton, Jr.)