Henry Gray (18251861). Anatomy of the Human Body. 1918.
of the muscle appears as an oblique elevation with a thick, rounded, anterior border, best marked in its lower part. The sternal heads of the two muscles are separated by a V-shaped depression, in which are the Sternohyoideus and Sternothyreoideus.
Above the hyoid bone, near the middle line, the anterior belly of the Digastricus produces a slight convexity.
The anterior border of the Trapezius presents as a faint ridge running from the superior nuchal line, downward and forward to the junction of the intermediate and lateral thirds of the clavicle. Between the Sternocleidomastoideus and the Trapezius is the posterior triangle of the neck, the lower part of which appears as a shallow concavitythe supraclavicular fossa. In this fossa, the inferior belly of the Omohyoideus, when in action, presents as a rounded cord-like elevation a little above, and almost parallel to, the clavicle.
Arteries.The positions of several of the larger arteries can be ascertained from their pulsations.
The subclavian artery can be felt by making pressure downward, backward, and medialward behind the clavicular head of the Sternocleidomastoideus; its transverse cervical branch may be detected parallel to, and about a fingers breadth above, the clavicle. The common and external carotid arteries can be recognized immediately beneath the anterior edge of the Sternocleidomastoideus. The external maxillary artery can be traced over the border of the mandible just in front of the anterior border of the Masseter, then about 1 cm. lateral to the angle of the mouth, and finally as it runs up the side of the nose. The pulsation of the occipital artery can be distinguished about 3 or 4 cm. lateral to the external occipital protuberance; that of the posterior auricular in the groove between the mastoid process and the auricula. The course of the superficial temporal artery can be readily followed across the posterior end of the zygomatic arch to a point about 3 to 5 cm. above this, where it divides into its frontal and parietal branches; the pulsation of the frontal branch is frequently visible on the side of the forehead. The supraorbital artery can usually be detected immediately above the supraorbital notch or foramen.