

THE EXTERNAL EAR 



1035 







muscle. In the cartilage of the auricula are two fissures, one behind the crus helicis and another 

 in the tragus. 



The ligaments of {he 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 (6) 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 in- ^1.^,1! ,iil n .. 



distinct. 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. 



The intrinsic muscles are the: 



Helicis major. 

 Helicis minor. 

 Tragicus. 



Antitragicus. 

 Transversus auriculae. 

 Obliquus auriculae. 



FIG. 906. The muscles of the auricula. 



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 auriculae is placed on the cranial surface of the pinna. It consists of scattered 

 fibers, partly tendinous and partly muscular, extending from the eminentia conchse to the promi- 

 nence corresponding with the scapha. 



The Obliquus auriculae, 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 auriculaj branch of the same nerve. 





