344 HEALTH AND DISEASE 



Insertion. — In front of the hock the teudou breaks up into several 

 branches, which become inserted into the front of the upper extremity of 

 the large metatarsal bone (canon) and into the small bones of the hock. 

 One of these branches passes over a synovial membrane on the cuneiform 

 parvum. 



Action. — To flex the hock. 



Extensor Brevis. — A short, flat, thin muscle situated in front and 

 below the hock -joint l)eneath the tendons of the extensor pedis and 

 peroneus. 



Origin. — From the outer part of the os calcis and the astragalus. 



Insertion. — Into the extensor pedis tendon. 



Action. — To assist the extensor pedis. 



POSTE-MOR ASPECT OF THE LEG 



Gastrocnemius. — A short stout muscle situated behind the leg. It 

 consists of two separate portions, which converge and unite below to form 

 a single strong tendon. 



Origin. — From either side of the supracondyloid fossa at the lower and 

 back part of the femur. 



Insertion. — Into the middle of the summit of the os calcis, or point of 

 the hock. A small synovial bursa is interposed between the anterior face 

 of the tendon and tlie portion of the os calcis in front of it. Bv this means 

 the parts move freely over each other when the hock is flexed. 



Prior to its insertion into the point of the hock the tendon of this 

 muscle is joined by that of another small muscle — the soleus. 



Action. — To extend the hock. 



Soleus. — A small muscle situated on the outer aspect of the leg. 



Origin. — From the outer surface of the head of the fibula. 



Insertion. — Into the tendon of the gastrocnemius. 



Action. — To assist in extending the hock. 



Flexor Pedis PerforatUS (Superficial Flexor of the Pastern). — This 

 is a round cord-like muscle in which tendinous tissue predominates. It is 

 placed in front of the gastrocnemius, which completely covers it. 



Origin. — From a deep depression (supracondyloid fossa) at the inferior 

 and posterior part of the femur. In passing down the leg the tendon of 

 this muscle gets behind the gastrocnemius tendon by winding round its 

 inner side. It then spreads out and becomes attached by means of short 

 tendinous slips to either side of the point of the hock to which it now 

 forms a cap. A small synovial bursa is interposed between the two parts 

 to facilitate the movement of one upon the other. 



