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 may be caused by severe muscular exertion. 
As a general rule, fractures are not frequent among 
animals. There are cases, 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 inte 
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