The prevertebral fascia is the posterior layer of the deep cervical fascia, enclosing the prevertebral muscles (longus capitis, longus colli) and the cervical vertebrae. It extends from the base of the skull to the coccyx as the anterior longitudinal fascia of the vertebral column. The scalene muscles and the brachial plexus are enclosed within an extension of the prevertebral fascia as the axillary sheath.
Encases the prevertebral muscles and cervical spine, forms the posterior wall of the retropharyngeal space, provides a closed compartment for infection localisation (retropharyngeal abscess), and extends as the axillary sheath enclosing the brachial plexus and axillary vessels.
The prevertebral fascia forms the posterior wall of the retropharyngeal space, allowing retropharyngeal abscesses to be confined before rupturing. In anterior cervical spine surgery, the prevertebral fascia must be opened along the anterior longitudinal ligament to access the cervical disc and vertebral bodies. Infection tracking along the prevertebral fascia can spread to the thoracic spine without producing mediastinitis. The axillary sheath derived from prevertebral fascia is the target for interscalene and axillary brachial plexus blocks.
Infection reaching the retropharyngeal space between the alar fascia anteriorly and the prevertebral fascia posteriorly produces a retropharyngeal abscess with fever, dysphagia, and anterior bulging of the posterior pharyngeal wall; CT confirms the abscess and management requires drainage either transorally or through an external cervical approach.
