1 5 2 APPLIED ANATOMY. 



nuchae it is attached up to the occipital protuberance. In the front of the neck it 

 passes from the mandible down to be attached to the hyoid bone and thence down- 

 ward to the sternum and clavicle. 



From the under side of this superficial layer processes of fascia come off and 

 envelop the various structures of the neck. Every separate structure of the neck 

 is covered by it and therefore separated from the adjacent parts by a more or less dis- 

 tinct layer of the fascia. In many places it is quite thin or almost imperceptible, 

 amounting to but a few shreds of fibrous tissue, in other places it is more distinct, 

 forming more or less marked capsules, as in the case of the thyroid and submaxillary 

 glands, or fibrous layers, as in the case of those in front of the vertebrae and trachea. 

 Posteriorly in the median line the superficial layer of the deep fascia sends a process 

 which covers the under surface of the trapezius muscle. Anteriorly another process 

 is given off to cover the under surface of the sternomastoid muscle. The super- 



Prevertebral fascia 

 Pneumogastric nerve 

 Common carotid artery 

 Internal jugular vein 

 Sheath of the vessels 



Superficial layer of deep fascia 



(Esophagus 



Trachea 



Thyroid gland 



Pretracheal fascia 



FIG. 178. Deep cervical fascia. The pharynx and larynx have been cut away, exposing the prevertebral and: 



pretracheal layers. 



ficial veins of the neck, the anterior, external, and posterior jugulars, lie on or in 

 the deep fascia, being stuck to or blended with its upper surface. 



About 3 cm. (i ]^ in.) above the sternum the deep fascia splits into two layers, 

 one to be attached to the anterior and the other to the posterior edge of the sternum 

 in front of the sternohyoid and sternothyroid muscles. Between these two layers is 

 the space of Burns ; it contains the lower ends of the anterior jugular veins with 

 the branch that joins them, some fatty tissue and lymphatic nodes, and the sternal 

 origin of the sternomastoid muscle. Sometimes a vein comes up from the surface of 

 the chest below to open into the anterior jugular vein. 



The prevertebral layer passes from side to side directly on the bodies of the 

 vertebras. It covers the muscles attached to the spine, as the scalene, longus colli, 

 rectus capitis anticus, and also the nerves, as those of the brachial plexus, coming 

 from the spine. On reaching the carotid artery and jugular vein it helps to form 

 their sheath. Its upper edge is attached to the base of the skull at the jugular fora- 

 men and carotid canal and thence across the basilar process to the opposite side. 

 Inferiorly it passes down on the surface of the bodies of the vertebrae into the pos- 

 terior mediastinum. 



