256 KENNEL DISEASES. 
CHAPTER II. 
FRACTURES. 
Tue composition of bones varies somewhat at different periods of life and in 
disease. For instance, during early life they contain proportionately more ani- 
mal or soft matter than mineral or hard matter, consequently the bones of pup- 
pies bend easily and seldom break, In old age there is a decided excess of 
mineral matter; there has been, also, a slight but steady absorption and reduc- 
tion in the size of bones, therefore the liability of fracture is then much greater. 
Again, there is a difference in the disposition to unite and heal readily, and after 
middle life the process is slower than in previous years; while in very old dogs 
there is marked reluctance to repair fractures. 
Rickets is the best illustration of the variability of the composition of bones in 
disease. While that exists they are weak, yielding, and easily broken. 
Bones of dogs are generally broken by direct violence, the force being ap- 
plied directly at the point of the facture, as a blow, from a fall, or the passage of 
a wagon-wheel over a leg. Less often fractures result from indirect violence, 
the force being applied at one part of the body, breaking a bone in another part, 
as a fall on the forefoot which breaks one of the upper bones of the leg. In 
very rare instances, also, small portions of bones have been broken off by what 
seemed enormous muscular strain, as required in making long or very high 
jumps. 
Fractures may be “ complete ” or “incomplete.” In the latter the bone may 
be cracked or splintered lengthwise, or bent or broken only half way through. 
A complete fracture extends entirely through the bone. A fracture is said to 
be “comminuted”’ when the bone is cracked or broken into several pieces. In 
an “impacted fracture” the same force that produced it drove one piece of bone 
into the other —in other words telescoped it and fixed it firmly. In a so-called 
“simple fracture” there is no open wound; but in a “compound fracture” a 
wound is made by either the same hard body that produced the fracture or by 
the ends of the bones forcing their way outward through the skin. A fracture 
may be simple or compound, and at the same time “complicated” if there is 
with it serious injury to other parts than the bone ; as for instance, when it opens 
into a joint, ruptures a large artery, lacerates or severs important nerves, or 
injures internal organs. 
The pronounced signs of fracture are pain, swelling, loss of power in the 
