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Home  »  Anatomy of the Human Body  »  pages 1035

Henry Gray (1825–1861). Anatomy of the Human Body. 1918.

pages 1035

muscle. In the cartilage of the auricula are two fissures, one behind the crus helicis and another in the tragus.
  The ligaments of the auricula (ligamenti auricularia [Valsalva]; ligaments of the pinna) consist of two sets: (1) extrinsic, connecting it to the side of the head; (2) intrinsic, connecting various parts of its cartilage together.
  The extrinsic ligaments are two in number, anterior and posterior. The anterior ligament extends from the tragus and spina helicis to the root of the zygomatic process of the temporal bone. The posterior ligament passes from the posterior surface of the concha to the outer surface of the mastoid process.
  The chief intrinsic ligaments are: (a) a strong fibrous band, stretching from the tragus to the commencement of the helix, completing the meatus in front, and partly encircling the boundary of the concha; and (b) a band between the antihelix and the cauda helicis. Other less important bands are found on the cranial surface of the pinna.
  The muscles of the auricula (Fig. 906) consist of two sets: (1) the extrinsic, which connect it with the skull and scalp and move the auricula as a whole; and (2) the intrinsic, which extend from one part of the auricle to another.
  The extrinsic muscles are the Auriculares anterior, superior, and posterior.
  The Auricularis anterior (Attrahens aurem), the smallest of the three, is thin, fan-shaped, and its fibers are pale and indistinct. It arises from the lateral edge of the galea aponeurotica, and its fibers converge to be inserted into a projection on the front of the helix.
  The Auricularis superior (Attolens aurem), the largest of the three, is thin and fan-shaped. Its fibers arise from the galea aponeurotica, and converge to be inserted by a thin, flattened tendon into the upper part of the cranial surface of the auricula.
  The Auricularis posterior (Retrahens aurem) consists of two or three fleshy fasciculi, which arise from the mastoid portion of the temporal bone by short aponeurotic fibers. They are inserted into the lower part of the cranial surface of the concha.
  Actions.—In man, these muscles possess very little action: the Auricularis anterior draws the auricula forward and upward; the Auricularis superior slightly raises it; and the Auricularis posterior draws it backward.


FIG. 906– The muscles of the auricula. (See enlarged image)
  The intrinsic muscles are the:
Helicis major.
Antitragicus.
Helicis minor.
Transversus auriculæ.
Tragicus.
Obliquus auriculæ.
  The Helicis major is a narrow vertical band situated upon the anterior margin of the helix.
  It arises below, from the spina helicis, and is inserted into the anterior border of the helix, just where it is about to curve backward.
  The Helicis minor is an oblique fasciculus, covering the crus helicis.
  The Tragicus is a short, flattened vertical band on the lateral surface of the tragus.
  The Antitragicus arises from the outer part of the antitragus, and is inserted into the cauda helicis and antihelix.
  The Transversus auriculæ is placed on the cranial surface of the pinna. It consists of scattered fibers, partly tendinous and partly muscular, extending from the eminentia conchæ to the prominence corresponding with the scapha.
  The Obliquus auriculæ, also on the cranial surface, consists of a few fibers extending from the upper and back part of the concha to the convexity immediately above it.
  Nerves.—The Auriculares anterior and superior and the intrinsic muscles on the lateral surface are supplied by the temporal branch of the facial nerve, the Auricularis posterior and the intrinsic muscles on the cranial surface by the posterior auricular branch of the same nerve.