ld 
THE NECK: ; 1179 
part of the anterior jugular veins along with their transverse communicating 
branch, a little fat, and one or two lymphatic glands. 
The vascular compartment, triangular in section, is bounded anteriorly by the 
general fascial envelope, which splits at the omo-hyoid to enclose the depressors of 
the hyoid bone; posteriorly by the prevertebral fascia; internally by the visceral 
compartment ; externally by the meeting of the prevertebral fascia and the pos- 
terior layer of the sterno-mastoid sheath. This compartment contains the carotid 
vessels, and the internal jugular vein, and the following nerves, viz.: the vagus, 
the first part of the hypoglossal, the descendens hypoglossi, and the upper part of 
the spinal accessory. The carotid chain of lymphatic glands lies in the cellular 
tissue which connects the various structures in the compartment; normally they 
may be readily separated from the sheath of the internal jugular vein, to which, 
Facial artery Anterior belly of digastric 
Submaxillary gland Hyoid bone 
Bifurcation of common carotid artery_ Thyroid cartilage (pomum Adami) 
+ ° ‘nie oS TYTO] =) ou: p 
Sterno-mastoid Crico-thyroid membrane 
Carotid tubercle L My yy 
se y Yy YY Y ae 
Apex of lung 
Li 
-External jugular vein 
Cricoid cartilage 
7 > Isthmus of thyrdid gland 
0 Sternal head of sterno-mastoid 
Sterno-clavicular articulation 
aa _Clavicular head of sterno-mastoid 
Z hs 
l]) i 
i 
Brachial plexus ~™ 
gt 
Subclavian arter WE 
Acromial end of clavicle 3 
Lesser tuberosity of \ 
humerus 
Tendon of biceps 
Greater tuberosity > 
of humerus \ 7 
_ 
m First part axillary artery 
| Coracoid process 
Pulmonary valve 
. . id by . 
Tricuspid valve Aortic valve 
| 
Mitral valve 
Fic. 799.—ANTERIOR ASPECT OF NECK AND SHOULDERS. 
however, they become adherent when inflamed. A glandular abscess in this com- 
partment usually points upon the surface, adhesions being formed, first, between 
the gland and the fascia, and, subsequently, between the latter and the cutaneous 
structures. In diffuse suppurative cellulitis of this compartment the pus burrows 
towards the root of the neck, and may reach either the mediastinum or the axilla. 
Middle Line of the Neck.—The body of the hyoid bone divides the middle line 
of the neck into supra- and infra-hyoid portions. Above the hyoid bone is the sub- 
mental triangle, with its apex at the lower border of the symphysis menti and its 
sides formed by the anterior bellies of the digastries. In the floor of the triangle 
are the anterior portions of the mylo-hyoid muscles, separated by the median 
raphe. The most important structures in the triangle are the supra-hyoid 
lymphatic glands, which can usually be felt a little above the body of the hyoid 
bone. They are a frequent seat of abscess secondary to impetigo of the lower lip 
