CHAPTER X 



DISEASES AND INJURIES OF THE BONES, LIMBS AND 



JOINTS 



Bones are composed of both mineral and organic 

 matter. In early life there is a predominance of the 

 animal or organic matter. As age advances the relative 

 proportion of mineral to animal material becomes 

 larger, the bones become harder and more brittle, and, 

 as a result, are more easily broken, and when broken 

 they do not unite as readily as do the bones of young 

 animals. This is an important fact in determining 

 whether or not it will pay to try to repair broken 

 bones in animals. 



FRACTURES 



A fracture is a break in a bone. It is usually 

 produced by external violence, although, in rare cases, 

 a fracture maj' be caused by severe muscular exertion. 

 As a general rule, fractures are not frequent among 

 animals. There are eases, however, in which the bones 

 are abnormally brittle and break easily. The bones of 

 young animals, being somewhat flexible, will sometimes 

 double up or bend out of place without cracking 

 when subjected to a severe strain. Such a condition 

 is commonly known as a "green-stick fracture," but it 

 is not frequently seen. When a bone is broken intc 



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