h jut out beyond the upper front
teeth, the mouth is open and cannot be closed, and the patient is
suffering considerable pain. When the jaw is dislocated on one side
only, the chin is pushed over toward the uninjured side of the face,
which gives the face a twisted appearance; the mouth is partly open
and fixed in that position. A depression is seen on the injured side
in front of the ear, while a corresponding prominence exists on the
opposite side of the face, and the lower front teeth project beyond
the upper front teeth.

[Illustration: FIG. 29.

REDUCING DISLOCATION OF JAW (AMERICAN TEXT-BOOK).

Thumbs placed upon last molar teeth on each side; note jaw grasped
between fingers and thumbs to force it into place.]

=Treatment.=--A dislocation of one side of the jaw is treated in the
same manner as that of both sides.

The dislocation may sometimes be reduced by placing a good-sized cork
as far back as possible between the back teeth of the upper and lower
jaws (on one or both sides, according as the jaw is out of place on
one or both sides), and getting the patient to bite down on the cork.
This may pry the jaw back into place.

The common method is for the operator to protect both thumbs by
wrapping bandage about his thumbs, or wearing leather gloves, and
then, while an assistant steadies the head, the operator presses
downward and backward on the back teeth of the patient on each side of
the lower jaw with both thumbs in the patient's mouth, while the chin
is grasped beneath by the forefingers of each hand and raised upward.
When the jaw slips into place it should be maintained there by a
bandage placed around the head under the chin and retained there for a
week. During this time the patient should be fed on liquids through a
tube, so that it will not be necessary for him to open his mouth to
any extent. (See Fig. 29.)

=DISLOCATION OF THE SHOULDER.=--This is by far the most common of
dislocations in adults, constituting over one-half of all such
accidents affecting any of the joints. It is caused by a fall or blow
on the upper arm or shoulder, or by falling upon the elbow or
outstretched hand. The upper part (or head) of the bone of the arm
(humerus) slips downward out of the socket or, in some cases, inward
and forward. In either case the general appearance and treatment of
the accident are much the same. The shoulder of the injured side loses
its fullness and looks flatter in front and on the side.