THE MUSCULAR SYSTEM 6 1 



this muscle is permanently shortened upon one side, the 

 resulting condition is known as torticollis, or "wry-neck." 



Sternohyoid. Arises from the sternum and calvicle. 

 Inserts into the hyoid bone. Action, depresses the hyoid 

 bone. 



Sternothyroid. Originates in the posterior part of 

 the sternum and cartilage of the first rib. Inserts into 

 the thyroid cartilage. Action, depresses the larynx. 



FIG. 33. Muscles of the neck from the front : On the left side the pla- 

 tysma has been removed, and on the right the digastric, the stylohyoid, 

 mylohyoid, sternohyoid, and omohyoid : i, Posterior, and i', anterior belly 

 of digastric ; 2, mylohyoid ; 3, geniohyoid ; 4, hyoglossus ; 5, styloglossus ; 6, 

 stylohyoid; 7, stylopharyngeus ; 8, stern omastoid ; 9, 9', omohyoid: 10, 

 Sternohyoid; n, 12, Sternothyroid; 13, levator scapulae. 



Thyrohyoid. Origin from the thyroid cartilage. 

 Insertion into the hyoid bone. Action, elevates the larynx 

 or depresses the hyoid bone. 



The omohyoid arises from the scapula, and is inserted 

 into the hyoid bone and cartilage of the first rib. Action, 

 depresses the hyoid bone and larynx and draws them 

 backward and to one side. 



Digastric. Arises from two heads, with an inter- 

 mediate tendon; is attached to mastoid process of the 

 temporal bone and lower jaw. Insertion, into the hyoid 

 bone. Action, raises tlie hyoid bone and depresses the 



