over the region escapes injury, but in the compound fracture the skin is
broken and the ends of the broken bone may protrude through it. The terms
complete and incomplete are used in describing fractures in which the ends
of the bones are not attached to each other, or partially so. In the
comminuted fracture the bone is broken into a number of pieces. There are a
number of other terms that may be used in designating the different kinds
of fractures, such as double, when both bones in the region are broken, and
oblique, transverse and longitudinal, depending on the direction of the
break.

_The causes_ of fractures may be divided into external or mechanical, and
internal. Fractures may result from kicks, blows, muscular strain and
contusions. Abnormal fragility due to disease, extreme youth and old age
are the internal predisposing factors.

_The symptoms_ are crepitation, abnormal movement and deformity of the
part. Abnormal movement of the part and inability to support weight occur
in fractures of the bones of the limbs. Crepitation or a grinding, rubbing
sound due to the movement of the ends of the broken bones on one another
occurs when the part is moved or manipulated with the hands. Pain, swelling
and injury to the skin are other local symptoms. The new tissue or bone
callus is formed by the bone-forming cells in the deeper layer of the
periosteum and bone-marrow.

_The prognosis is unfavorable._ The larger percentage of fractures in
domestic animals are incurable, or make an unsatisfactory recovery. This is
due to careless treatment, the character of the fracture and the inability
to fix the ends of the broken bone. Fractures in young and small animals
usually heal quickly. Individuals that are healthy and vigorous usually
make a speedy recovery. Fractures heal very slowly in the aged. Compound