Anatomy of the Cervical Spine

The vertebral column is divided into regions and consists of 32-35 vertebrae, separated from each other by intervertebral discs. Functionally, the vertebrae form a single structure designed to maintain an upright posture and balance countering gravity, enabling locomotion and every other kinetic movement against applied force and resistance. Therefore, the two basic requirements of the spine are rigidity, for static efficiency and protection of the spinal cord and spinal nerves, and flexibility, for the kinematics of the spine. Vertebrae forming the different parts of the spine have joints that allow diverse spine movements, such as rotation, inclination, flexion and extension of the head. The cervical spine is mainly innervated by the cervical plexus. The cervical plexus is composed of the anastomosis of ventral branches of the first four cervical nerves and by an anastomotic branch of fifth one, forming the ansa cervicalis.