prevertebral fascia
The deep layer of the deep cervical fascia is one of the three layers of the deep cervical fascia. It encases the paravertebral muscles and forms the perivertebral space. It consists of the perivertebral fascia (the anterior part of which is called the prevertebral fascia) and alar fascia .
Gross anatomy
Attachments
- posteriorly
- ligamentum nuchae
- cervical vertebral spinous processes and transverse processes
- laterally
- carotid sheath
- first rib (from portion of the layer called Sibson fascia)
- axillary sheath
- superiorly
- skull base
- inferiorly
- coccyx (for the prevertebral fascia)
- endothoracic fascia (for the alar fascia)
On each side, a flap attaches to the transverse processes of the cervical vertebrae and divides the peri-vertebral spaces into a pre-vertebral compartment anteriorly and a para-spinal compartment posteriorly .
Anteromedial to the scalene muscles, the deep layer splits into two leaves; the ventral leaf being the alar fascia, and the dorsal leaf being the prevertebral fascia (with the prevertebral space being between the prevertebral fascia and the spine). The space between the alar fascia and the prevertebral fascia is the danger space. The space between the alar fascia and the posterior aspect of the middle layer of the deep cervical fascia is the retropharyngeal space.
Contents
- danger space (between prevertebral and alar fascia)
- prevertebral space (anterior component of perivertebral space)
- longus colli and capitis muscles
- rectus capitis anterior and lateralis muscles
- scalenus anterior, medius, and posterior muscles
- sheath for subclavian artery and vein, brachial plexus
- vertebral column
- spinal cord and associated thecal sac, nerve roots, and vessels
- vertebrae and associated discs and ligaments
- paraspinal/paravertebral space (posterior component of perivertebral space)
- levator scapulae
- deep cervical back muscles
- pierced by the four cutaneous branches of the cervical plexus
In addition, all layers of the deep cervical fascia contribute to the carotid sheath.