Neck and Upper Back Injuries

Anatomy

The neck and upper back play an important role in motion and support of the upper body and head. The neck, or cervical spine, provides motion and support for the skull. The upper back, or thoracic spine, allows for the transfer of forces between the upper and lower extremities. Together, the cervical spine and thoracic spine contain the spinal cord.

The flexible cervical spine is at greater risk of injury to the disks and bony structures because of its inherent mobility. The thoracic spine, however, is more rigid and isprotected by the rib attachments. The lower two ribs are unattached (“floating”) and allow increased motion in the lower thoracic spine. Traumatic and overuse injuries of the spine are more common in the transition zones of flexibility at the lower cervical and thoracic spine.

The cervical vertebrae can be divided into the upper and lower cervical spine. The upper cervical spine consists of the occiput to C1 and the C1-C2 articulation. The atlas, C1, has a smaller arch in the front and a larger arch in the back, which are connected by the lateral masses. The axis, C2, contains the odontoid process, which articulates with the anterior arch of C1. It is held in place by the transverse ligament. Forty percent of cervical flexion and extension and 60% of rotation occur between the occiput to C1 and C1-C2 articulations.

The lower cervical spine is principally responsible for flexion and extension. The lower cervical spine consists of the C3-C7 vertebral bodies, separated by the intervertebral disks. The facet joints form the posterior border of the foramina and lie in a horizontal plane, allowing for rotation. In the thoracic spine, the facet joints are more vertical. The transverse process contains the vertebral artery foramen.

The size of the thoracic vertebrae gradually increases from T1 through T12. The heads of the ribs articulate with the facets on the vertebral bodies. The tubercles of the ribs articulate with the facets on the transverse processes. The thoracic facet joints are in a coronal orientation that allows for lateral flexion of the thoracic spine. There is a transition between the upper and lower thoracic vertebrae. The upper vertebrae resemble cervical vertebrae, whereas the lower thoracic vertebrae more closely resemble lumbar (lower back) vertebrae. An additional structure unique to the thoracic spine is the scapula (shoulder blade). The scapula is a triangular bone that lies between the second and the seventh ribs and projects 30° to 40° to the frontal plane. There are several fluid-filled sacs called bursae, which help in the movement of the shoulder blade over the posterior ribs.

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