Page:Muscles and Regions of the Neck.djvu/3

 NECK. Gr. τραχηλος; Lat. 'collum, cervir; Fr. le cou; Ital. il collo; Ger. der Hals. This word denotes that contracted, ribless portion of the trunk or column of support, which, in vertebrate animals, immediately sustains the head. Disease and accidental lesions so frequently submit it to surgical examinations and operative treatment, that familiar acquaintance with its intricate anatomy is of indispensable necessity to the practitioner.

The order which I shall adopt in the ensuing article is, first, to describe fully and in order the muscles and fasciæ of the neck, and subsequently the various regions into which it may be divided with the parts contained in them; the earlier portion giving, as it were, a mere skeleton view or diagram of the anatomy; the latter presenting the organs in their more natural, or regional arrangement, and treating of them in their living relations to disease, casualty, and surgical operation. I should recommend the student of this important part to pursue a similar plan; first, namely, thoroughly to impress on his mind those relatively firm and fixed textures which admit of practical use as landmarks, and not, till this task is completed and these anatomical boundary lines are vividly and individually before him, to fill up his sketch with important organs, or perplex his mind with their surgical relations.

The muscles of the posterior region of the neck and those of the shoulder having been described in a previous article (see ), the remainder may be considered in three classes—1. those which most nearly cleave to the vertebræ, are attached to their processes, and principally affect their motions; 2. those, chiefly in or near the median plane, which belong to the cervical portions of the respiratory and digestive apparatus, to the pharynx, larynx, tongue, and os hyoides; 3. the superficial muscles of the side of the neck, the sternocleido-mastoideus, and the platysma myoides. The first class includes—1. anteriorly, the longus colli and rectus capitis anticus major; 2. laterally, the scalenus anticus, scalenus posticus, and inter-transversales, with which may be reckoned the rectus capitis lateralis and rectus capitis anticus minor.

1. ''Anterior vertebral muscles—M. longus colli (Pre-dorso-utloidien:'' Chauss.) is a thin elongated muscle, which occupies an extent in the pre-vertebral region, corresponding to the three upper dorsal and to all the cervical vertebræ. In form it is triangular, having its base at the bodies of these vertebræ, and its truncated apex at the middle transverse processes of the cervical region, and consists of three distinct, though united, parts, which would be represented by the three sides of such a triangle. One portion, the largest, is nearly vertical, next to the median line, and a direct flexor of the spine: it originates from the bodies of the three upper dorsal and four lower cervical vertebræ, as also from the intervening fibro-cartilages, and, ascending, is inserted by two slips into the anterior surface of the bodies of the second and third vertebræ. Tie second part is directed from the transverse processes of the third, fourth, and fifth cervical vertebræ, at which it arises by tendinous slips,—upward and inward to be inserted into the anterior tubercle of the atlas, and it so continues to that bone the previous insertion of the muscle. The remaining part detaches itself from the main body of the muscle at the bottom of the neck, and ascends obliquely outward, to infix itself by small tendons at the anterior tubercles of the transverse processes of the third and fourth cervical vertebræ. The muscle may, in short, be described as passing from the bodies of the three upper dorsal and four lower to those of the three remaining cervical vertebra, receiving above an oblique reinforcement from the middle transverse processes of the neck, to which it has likewise below detached slips of insertion.

M. rectus cupitis unticus major (Grandtrachelo-basilaire: Dumas) lies closely on the vertebræ in the upper part of the neck, to the outside of the preceding muscle. It is an elongated, but thickish, muscle, arising by tendinous slips from the anterior tubercles of the transverse processes of the third, fourth, and fifth cervical vertebræ. These become fleshy, unite as they ascend, and are inserted into the under surface of the basilar process of the occipital bone, beside the median line, and just behind the spine, which attaches the raphe of the pharynx. Its inner edge overlaps the longus colli. These muscles correspond anteriorly to the great vessels of the neck, to the nerves which accompany them, and to the cervical portions of the respiratory and digestive tubes, but are separated by their own dense fascia from immediate relation to these parts. Their deep surface is in intimate connection with all the vertebræ and intervertebral discs, to which they correspond. Their action is inconsiderable; the rectus will slightly rotate and bend the head to its own side, or in conjunction with its fellow directly flex it. The longus colli, cooperating with its fellow, bends the cervical spine; or, acting singly, can slightly rotate by its higher fibres toward, by its lower fibres away from, the side on which the contraction occurs.

2. Lateral vertebral muscles.—The intertransversales colli are almost described by their name. They form, on each side, a double series of small square muscles, occupying the spaces between the adjoining transverse processes, which afford them attachment by both borders of their surface. Arising from the lips, which the channelled upper surface of each transverse process presents, they ascend in each space to the borders of the process immediately above, and are there inserted. Between the intertransversales antici and postici the spinal nerves of the region emerge, and the vertebral artery ascends.

Strictly analogous to these are the two small muscles which pass to the occiput from the transverse process of the atlas, the rectus cupitis lateralis and rectus capitis anticus minor. The former would represent a posterior, the latter an anterior inter-transversalis. The former