NECK. 



571 



viewed connectedly), it may be well to take 

 them in that relation. 



Thus, (1) a region of the median line, (2) an 

 antero-inj'erior, (3) an antero-svperior, (4) a 

 postero-superior, and (5) a postero-inferior t/ : t- 

 angle, (6) a digastric, and (7) a posterior p/ia- 

 ryngeal space, are to be severally considered ; 

 and a few preliminary remarks may be given 

 to the tegumentary parts, which are more or 

 less common to all. 



The skin is fine, thin, and extensible, espe- 

 cially below and in front; becoming coarser 

 and more adherent toward the upper part of 

 the posterior triangle ; it frequently presents 

 some transverse wrinkling above the hyoid 

 bone, which seems to depend on the platysma 

 myoides; here, too, the follicles are larger and 

 more abundant than in the other parts of 

 the neck, and, in the male subject, the surface 

 is overgrown by the beard. The subcutaneous 

 cellular tisane has already been described ; in 

 the upper part of the posterior triangle it be- 

 comes almost inseparably confounded with the 

 cervical aponeurosis; the pltttysina myoides lies 

 between its layers and keeps them apart 

 over the greater surface of the neck ; the 

 fibres of this muscle are absent in the lower 

 part of the anterior, and upper part of the 

 posterior triangle, and at these spots the two 

 layers of the superficial fascia fall together and 

 are nearly confounded. In the deeper lamina 

 of this texture, subjacent to the platysma in the 

 parts where it lies, run the superficial veins and 

 nerves. The external jugular vein commences 

 in the parotid gland, usually by radicles, which 

 correspond to the terminal branches of the ex- 

 ternal carotid artery, temporal, internal maxil- 

 lary, and transverse facial ; pierces the fascia 

 near the angle of the jaw, und directs itself al- 

 most vertically toward the middle of the cla- 

 vicle, in the deep layer of superficial fascia : 

 just at the edge of the clavicular insertion of 

 the sterno-mastoid muscle it bends inward, 

 pierces the aponeurosis, and discharges itself 

 into the subclavian vein. It thus very ob- 

 liquely crosses the sterno-cleido-mastoideus 

 from its anterior to its posterior edge, sepa- 

 rated from that muscle by its fascial sheath ; 

 the auricular nerve runs upward parallel 

 to its posterior border ; the platysma covers 

 it in its whole course with fibres which cross 

 its direction ; its place of discharge into the 

 subclavian vein is usually just opposite the 

 sealenus anticus, covered by fascia and by the 

 sterno-mastoid muscle. It receives superficial 

 occipital, superior and posterior scapular veins ; 

 branches from the posterior triangle of the 

 neck, and from the trapezius; it has uncertain 

 and irregular communication with the anterior 

 jugular vein, and receives a certain, though not 

 regular, branch from the internal jugular ; this 

 is usually given to it at the lower part of the 

 parotid, or on its emergence from that gland, 

 and occasionally seems to constitute its com- 

 mencement. Obvious surgical inferences from 

 the anatomy of this vein are : the relief that its 

 communication with the internal jugular en- 

 ables it to give, when opened in cases of cere- 

 bral congestion ; the eligibility of its line of 



passage over the thick belly of die sterno- 

 mastoid for that mode of venesection ; the ne- 

 cessity for dividing some fibres of the platysma 

 transversely to theirlength (by an incision nearly 

 in the direction of the sterno-mastoid) in order 

 to obtain a clear opening and free jet of blood ; 

 the need for c;ire in this operation, but still 

 more in proportion as the vein is wounded 

 lower in the neck, to hinder the possibility of 

 air being inspired through its cavity. 



The aitterwr jugular vein is an irregular sub- 

 cutaneous su implement to the external : it com- 

 mences in thesubmental region, near the hyoid 

 bone; descends vertically beside the median 

 line, receiving branches from the larynx, and 

 sometimes from the thyroid body ; on arriving 

 at the sternum, or near that bone, it bends 

 horizontally outward, piercing the fascia, and 

 runs behind the origin of the sterno-mastoid, to 

 throw itself into the subclavian vein, somewhat 

 within the termination of the external jugular. 

 It generally has free communications with its 

 fellow and with the internal and external ju- 

 gular. Its size is in inverse proportion to that 

 of the external; and, in absence of this, it is 

 generally a very considerable branch; it is 

 sometimes single and mesial ; but more usually 

 two exist, which are commonly of unequal 

 calibre. 



The superficial nerves are of two classes, 

 being partly derived from the cervical plexus, 

 partly from the portio dura. 



The cervical plexus sends its superficial 

 branchings in three directions : the mastoid and 

 auricular pass upward ; the anterior cervical 

 runs forward ; the snpra-cluvicular and super- 

 acromial, as their names denote, descend more 

 or less obliquely. 



The mastoid, originating from the second 

 cervical nerve, winds upwardly across the sple- 

 nius, and almost parallel with the posterior edo-e 

 of the sterno-imstoid, which it crosses in its 

 ascent. It pierces the fascia soon after its 

 origin, and becomes subcutaneous. Its distri- 

 bution is entirely to the skin of the mastoid and 

 occipital regions. The auricular, rising from 

 the second and third cervical nerves by a trunk, 

 common to it with the anterior cervical, di- 

 rectly pierces the fascia, loops round the pos- 

 terior edge of the sterno-mastoid, and ascends 

 across its surface (the fascial sheath intervening) 

 toward the angle of the jaw; where, after sup- 

 plying twigs to the integuments over the pa- 

 rotid gland, it divides into terminal branches, 

 which are distributed to the external and in- 

 ternal surfaces of the auricle and to the adjoin- 

 ing integument, in a manner which need not 

 be particularised in the present article. In 

 crossing the sterno-mastoid it is parallel to the 

 external jugular vein, and behind it. The 

 anterior cervical rises in common with the last, 

 and pierces the fascia in its company; bends 

 at right angles across the sterno-mastoid muscle, 

 and is itself crossed by the external jugular vein. 

 On arriving at the edge of the muscle, it di- 

 vides into many twists, which, traversing the 

 platysma at several spots, distribute themselves 

 to the skin of the antenor triangle of the neck, 

 and to that of the adjacent part of the digastric 



