THE NECK. 



The superficial lymphatic nodes frequently suppurate. When they do the 

 abscess so formed is prevented by the deep fascia from reaching the parts beneath, so 

 the pus works its way out through the skin. As the superficial fascia is loose, if 

 the abscess is slow in formation, it may extend for a considerable distance under the 

 skin. 



Sebaceous cysts are common in the neck. As they are superficial to the deep 

 fascia, which is not involved, they can be removed without fear of wounding any 

 important structures. The veins do not overlie them; they are always superficial 

 to the veins, therefore there is no danger of wounding the external jugular. 



The Deep Cervical Fascia. The deep cervical fascia completely envelops 

 the neck and sends its branches in between all its various structures. It is the 

 fibrous tissue that both unites and separates all the different structures to and from 

 each other. Where this fascia is abundant it forms a distinct layer, but where it is 

 scant it is simply a small amount of connective tissue between two adjacent parts. 



Anterior jugular veins 



Larynx 



Superficial layer of deep cervical fasci 

 Pretracheal layer 

 CricoidcartL 



Cricothyroid muscle 

 Prevertebral layer 

 Longus colli 



Sternohyoid muscle 

 Sternothyroid 

 Thyroid gland 

 Omohyoid 



Carotid artery 

 Sternomastoid 



Trachelomastoid 



Sixth vertebra 



Longus colli 



Internal jugular vein 

 Trachelomastoid 



Scalenus anticus and medius 



External jugular vein 

 Scalenus posticus 



Levator scapuUe 

 Splenius colli 

 Splenius capitis 



Trapezius 



;omplexus 

 Multifidus spinae 

 Semispinales cervices 



FIG. 177. Transverse section of the neck through the sixth cervical vertebra. 



To follow all the processes of the deep fascia through the neck between its innumer- 

 able structures is impossible nor is it necessary. The main reason for studying the 

 deep cervical fascia and its various parts is to understand the course pursued by 

 abscesses and infections. This is best done by limiting oneself to the main super- 

 ficial layer and some of the larger layers crossing from side to side. 



The principal layers of the deep cervical fascia are the superficial layer, which 

 completely encircles and envelops the neck, the Prevertebral layer, which passes 

 from side to side in front of the spinal column, and the pretracheal layer, which passes 

 from side to side in front of the trachea. 



The Superficial Layer. The superficial layer of the deep fascia envelops the 

 whole of the neck, with the exception of the skin, platysma, and superficial fascia. 

 It is attached above to the occipital protuberance, the superior curved line of the occi- 

 put, the mastoid process, then blends with the capsule of the parotid gland, then passes 

 to the angle of the jaw and along the body of the mandible to the symphysis, 

 whence it proceeds around the opposite side in the same manner. Below it is 

 attached to the sternum, upper edge of the clavicle, acromion process, and spine of 

 the scapula, thence across to the vertebral spines, to which and to the ligamentum 



