ation exists, therefore, the limb should
be fixed at an acute angle, and movements of full extension postponed
for a fortnight. Massage and limited movements, however, may be
carried out from the first.

If there is a fracture of the olecranon, the treatment must be
modified accordingly (p. 87).

[Illustration: FIG. 39.--Forward Dislocation of Elbow, with Fracture
of Olecranon.

(Sir Robert Jones' case. Radiogram by Dr. D. Morgan.)]

Comminuted and compound injuries usually call for operative treatment,
the fractured bones being wired after reduction of the dislocation, or
the loose fragments removed.

The _forward dislocation_ is reduced by fully flexing the elbow, and
then pushing the bones of the forearm backward, while the humerus is
pulled forward.

_Old-standing Dislocations._--No attempt should be made to reduce by
manipulation a dislocation of the elbow which has remained displaced
for five or six weeks, especially when it has been complicated by a
fracture. The joint surfaces become welded together by adhesions, and
separated fragments often form attachments which lock the joint.
Attempts to break these down are attended with considerable risk of
re-fracturing the bone or of tearing the soft parts. In such cases it
is best to expose the joint, and if reduction is not easily effected a
sufficient amount of the lower end of the humerus should be removed to
provide a movable joint.

#Dislocation of the ulna alone# is a rare injury, and is usually
associated with fracture of one or other of its processes or of the
inner condyle.

#Dislocation of the radius alone#, on the other hand, is comparatively
common, especially as a concomitant of fracture of the upper third of
the shaft of the ulna (Fig. 40).

The injury may result from a blow on the back of the upper end of the
radius, a fall on the outstretched hand, or, in children, from
forcible traction on the forearm while in the pronated position. The
displaced head usually passes _forward_, and rests on the anterior
edge of the capitellum, thus preventing complete flexion and
supination of the limb.

The limb is held partly flexed and pronated. The displaced head of the
radius can be felt to rotate with the shaft in its abnormal position,
and the articular facet on the head of the radius may also be felt;
there is a depression posteriorly below the lateral epicondyle where
the head should be. The radial side of the forearm is slightly
shortened. The s