Editing Cervical vertebrae (section)

==Function==

The movement of nodding the head takes place predominantly through [[Anatomical terms of motion|flexion]] and [[Anatomical terms of motion|extension]] at the [[atlanto-occipital joint]] between the atlas and the [[occipital bone]]. However, the cervical spine is comparatively mobile, and some component of this movement is due to flexion and extension of the vertebral column itself. This movement between the atlas and occipital bone is often referred to as the "yes joint", owing to its nature of being able to move the head in an up-and-down fashion.

The movement of shaking or rotating the head left and right happens almost entirely at the joint between the atlas and the axis, the [[atlanto-axial joint]]. A small amount of rotation of the vertebral column itself contributes to the movement. This movement between the atlas and axis is often referred to as the "no joint", owing to its nature of being able to rotate the head in a side-to-side fashion.