FRACTURES. 257 
leg, change in the outward appearance of the injured parts, ability to move por- 
tions of the leg below the injury in ways and directions which would not be 
possible were it uninjured, and a low grating sound, called crepitus, to be heard 
near the broken ends of the bone when they are twisted or rubbed over each 
other. 
In other words, one may be reasonably certain that a bone is broken when 
its shape is changed, pain is caused by every movement, and a crackling sound 
is heard or a crackling felt by the examiner as he moves the parts. A broken 
bone is generally shortened; the muscles above and below the place of fracture 
drawing the two pieces so as to overlap each other. When the break is near a 
joint it is sometimes difficult to determine whether there is a fracture or a dis- 
location; and the difficulty is much increased if the examination is not made 
until several hours after the accident and inflammation has set in, attended 
by swelling. 
While it is sound, a leg is sure to be like its fellow on the opposite side. 
If after an accident there is a change in the shape of a leg there must be 
either a dislocation or a fracture; and to distinguish between the two should 
rarely be difficult. To produce the grating or crepitus, grasp the parts above 
and below the injury and gently endeavor to rub the ends of the bone together, 
or slightly twist the lower part. 
A fracture may be mistaken for a severe bruise, or for a sprain, as well as for 
a dislocation. If the injured dog is not examined until several hours after his 
accident and there is much swelling and inflammation, it may be that to at once 
determine the nature of the injury will not be possible, nor until after applica- 
tions of hot or cold water have been made to reduce the swelling. 
In a simple bruise there is merely pain and swelling, and possibly some loss 
of power in the leg, with slight changes in its appearance. But there is no un- 
natural motion below the point of injury, and no grating sound, as between the 
two ends of a broken bone. A sprain also lacks these last signs. As for the 
means of discriminating between a fracture and a dislocation, they have been 
already described. 
As a rule, broken bones will unite if their ends are brought together and 
kept in place. In very rare instances, however, they fail to do so and a so-called 
false joint is formed; the bones are either not united at all and easily movable 
on each other, or they are held together more or less firmly by cartilage or liga- 
ments. Sometimes also the false joint very closely resembles a true joint. 
If broken bones are not properly set or kept in place there is deformity. 
They may unite at an angle, making a crooked leg; or if there is destruction of 
a portion of a bone or overlapping of its fragments, the leg is shortened. Joints 
may also be rendered stiff by fractures which are near but do not enter them. 
In the treatment of fractured bones the first two essentials are to get the 
broken parts into their right places and keep them there until they unite or 
