Os Odontoideum

The structures of the neck include the cervical portion of the spine, consisting of seven cervical vertebrae. The top two vertebrae, C1 (atlas) and C2 (axis), have an anatomy different from that of the lower cervical vertebrae to provide for much of neck rotation and nodding. In the lower cervical vertebrae, C3 through C7, each vertebra has an anterior cylindrical structure called the vertebral body, with a posterior bony canal housing the spinal cord. Each vertebral body is separated above and below by a cervical disk. At the ...