580 



DISSECTION OF THE NECK. 



ascending, 



descending 

 branch. 



Branch of 

 facial nerve 

 to the neck 



Dissection. 



Cervical 

 fascia in 

 front of 

 sterno- 

 mastoid. 



Intermus- 

 cular strata. 



neck. Beneath the platysma it divides into an upper and a lower 

 branch : 



The upper branch perforates the platsyma, and ends in the skin 

 over the anterior triangle, extending about half way down the 

 neck. While beneath the platysma this branch joins the facial 

 nerve. 



The lower branch likewise passes through the platysma, and is 

 distributed to the integuments below the preceding, reaching as 

 low as the sternum. 



The INFRAM AXILLARY BRANCH OF THE FACIAL NERVE (p. 564) 



pierces the deep cervical fascia, and divides into slender offsets 

 which pass forwards beneath the platysma, and form arches across the 

 side of the neck (fig. 205), reaching as low as the hyoid bone. 

 Most of the branches end in the platysma, but a few filaments 

 perforate it, and reach the integuments. Beneath the muscle there 

 is a communication between this branch of the facial and the upper 

 division of the superficial cervical nerve. 



Dissection. Cut across the external jugular vein about the 

 middle, and throw the ends up and down. Afterwards the super- 

 ficial nerves of the front of the neck may be divided in a line with 

 the angle of the jaw, the anterior ends being removed, and the 

 posterior reflected. The great auricular nerve may be cut through 

 and the ends reflected. 



The part of the DEEP CERVICAL FASCIA in front of the sterno- 

 mastoid is stronger than that over the posterior triangle, and 

 has the following arrangements. Above, it is fixed to the base of 

 the lower jaw, and is continued over the parotid gland to the 

 zygoma. A thickened band passes backwards from the angle of 

 the jaw to the sheath of the sterno-mastoid, and holds forwards the 

 anterior border of that muscle. Above this, a deep process is sent 

 inwards from the hinder margin of the ramus of the jaw, between 

 the parotid and submaxillary glands, to the styloid process, giving 

 rise to the stylo-maxillary ligament. In front, the fascia is attached 

 to the body of the hyoid bone ; and below, to the sternum. Its 

 lower part forms a dense white membrane, which near the 

 manubrium becomes divided into two layers, one passing in front 

 and the other behind that bone, so as to enclose a small space 

 above it containing a little fat and the transverse branch of 

 communication between the anterior jugular veins. 



Layers of the membrane are prolonged between the muscles ; and 

 that beneath the sterno-mastoid is continuous with the sheath of 

 the cervical vessels. One of these, beneath the sterno-thyroid 

 muscles, descends in front of the great vessels at the root of the 

 neck to the arch of the aorta and the pericardium. 



ANTERIOR TRIANGULAR SPACE. 



Anterior This space (fig. 211, p. 582) contains the carotid vessels and their 



space gnli branches, with many nerves ; and it corresponds with the hollow 

 on the surface of the neck in front of the sterno-mastoid muscle. 



