SUPERFICIAL EXAMINATION 7 



Assuming that the "near" hock is the one to be examined, the student 

 should first stand with his face directed towards the horse's head, and 

 should pass the palmar aspect of his right hand over the front of the 

 hock. In this manner the tracing of the tendon of the extensor pedis 

 may be made, and the tendon may be caused to stand out prominently 

 if the hock be flexed. The main portions of the tendons of the flexor 

 metatarsi muscle may also be traced to their insertion into the anterior 

 face of the upper extremity of the large metatarsal bone, though these 

 tendons are not quite so evident as is that of the extensor pedis. 



On the inner aspect of the joint two prominent elevations are seen, 

 the upper of which is caused by the internal malleolus of the tibia, 

 and the one below it by the well-defined tubercle on the inner surface 

 of the astragalus. The tubercle just mentioned varies considerably in 

 size in different animals. The size of the tubercle is not a matter 

 of great consequence, provided both tubercles are alike and well 

 defined. The tubercle is only in rare and advanced cases involved in 

 spavin, and when such happens it loses its well-defined outline, and in 

 its place we have a diffused enlargement. 



Running almost vertically across the internal malleolus of the tibia 

 is a faint depression which, when we come to study the deeper 

 anatomy of the joint, we shall find gives passage to a tendon, namely, 

 that of the flexor accessorius muscle. 



The usual seat of spavin is on the antero-internal aspect of the 

 inferior third of the joint, and the touch of the fingers should be care- 

 fully educated to appreciate the exact normal conformation of this area. 

 This is only brought about by constant practice, since the difference in 

 external contour presented by a normal hock and many hocks affected 

 with spavin is so slight that it is only appreciable to a sense of touch 

 which has been cultivated to a considerable degree of delicacy. 



Below the elevation caused by the tubercle of the astragalus a slight 

 horizontally disposed elevation is found which curves round from the 

 anterior to the internal aspect of the joint. This elevation corresponds 



