HIND EXTREMITIES. 103 



THE HOCK. 



82. — Of all the joints in the body this is the most 

 important. We must refer the reader to our de- 

 scription of the bones in Lesson VIII, and remind 

 him that according to the size of the individual 

 bones alone the apparent size of the hock does not 

 depend, but more upon the angle at which the tibia 

 impinges upon the astragalus. This is well seen in 

 extreme flexion, when the hock seems to disappear 

 leaving nothing but its so called point in view. 

 The lower fourth or more of the hock is made up of 

 the buffer bones in front and at the sides, conse- 

 quently it is these which give the lower part of the 

 hock size. They must be large but not necessarily 

 coarse, but they may be large and coarse and of un- 

 equal size in the two hocks and yet be quite healthy 

 and free from ' spavin.' The top of the metatarsal 

 bone on which they mainly rest must also be large. 

 When this latter is small we have a grave defect ; 

 but when it is not only small, but forms with the 

 buffer bones of the hock an angle, we have a very 

 grave defect called ' curby hocks.' 



The hock should present on its inner surface a 

 hig^ flat, square appearance, and when a horseman 

 speaks of liking a big, flat, square hock, he refers 

 to the inner aspect of the hock. The boundaries 

 of this so-called square are as follows : the internal 

 maleolus or lowest inner point of the tibia ; the 

 extreme point of the hock ; the front part of the 

 head of the tibia ; lastly, the head of the small 



