![]() Median sagittal section through the occipital bone and first three cervical vertebræ, showing ligamentous attachments The atlas and axis are important neurologically because the brainstem extends down to the axis. It is ring-like and consists of an anterior and a posterior arch and two lateral masses. The atlas's chief peculiarity is that it has no body. The dens acts as a pivot that allows the atlas and attached head to rotate on the axis, side to side. The atlanto-occipital joint allows the head to nod up and down on the vertebral column. They are responsible for the nodding and rotation movements of the head. The atlas and axis are specialized to allow a greater range of motion than normal vertebrae. The atlas is the topmost vertebra and, with the axis (the vertebra below it), forms the joint connecting the skull and spine. Scholars believe that by switching the designation atlas from the seventh to the first cervical vertebra Renaissance anatomists were commenting that the point of man’s burden had shifted from his shoulders to his head-that man’s true burden was not a physical load, but rather, his mind. Sometime around 1522, anatomists decided to call the first cervical vertebra the atlas. Ancient depictions of Atlas show the globe of the heavens sitting at the base of his neck, on C7. In Greek mythology, Atlas was condemned to bear the weight of the heavens as punishment for rebelling against Zeus. However, the term atlas was first used by the ancient Romans for the seventh cervical vertebra (C7) due its suitability for supporting burdens. The bone is named for Atlas of Greek mythology, for just as Atlas bore the weight of the heavens, the first cervical vertebra supports the head. In anatomy, the atlas (C1) is the most superior (first) cervical vertebra of the spine and is located in the neck.
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