The cervical spine consists of seven vertebrae and is located at the base of the skull. Its function is to support the skull, enabling head movements back and forth, and from side to side, as well as protecting the spinal cord. The upper section of the cervical spine consists of the first cervical vertebrae (C1) and the second cervical vertebrae (C2). The lower section consists of the third cervical vertebrae (C3) through seventh cervical vertebrae (C7). These spinal bones attach to the thoracic spine and work together to support the head. The fourth cervical vertebra (C4) is centrally located in the cervical (or neck) region of the spinal column. This is just above the thoracic vertebrae. Together, the C4 and C5 vertebrae are also located in close proximity to the thyroid cartilage.
Similar to other cervical vertebra, C4 is uniquely shaped when compared to most other bones in the entire body. The vertebra is made up of a body and a transverse process. The pedicle and lamina have left and right designations, and collectively, they form the bone that surrounds the spinal cord. The left and right lamina meet in the spinous process. The fourth cervical vertebra (C4) may be damaged for a number of reasons, but injury is most commonly caused by high-impact trauma. If it fails to protect the spinal column, complete or total paralysis may result. Spinal damage can be common up to the second cervical vertebra.