caused by the lower end of the ulna. The radial styloid is displaced
forward, upward, and to the radial side, and the ulnar styloid may be
torn off.

[Illustration: FIG. 47.--Radiogram of Smith's Fracture.

(Sir George T. Beatson's case.)]

When the deformity is not well marked, this injury may be mistaken for
forward dislocation of the wrist, for fracture of both bones low down,
or for sprain of the joint.

The _treatment_ is carried out on the same lines as in Colles'
fracture.

_Longitudinal fractures_ of the lower end of the radius opening into
the joint usually result from the hand being crushed by a heavy weight
or in machinery. They are often compound and comminuted.

#Separation of the lower epiphysis# of the radius, which is on the
same level as that of the ulna and lies above the level of the
synovial membrane of the wrist-joint, is comparatively common between
the ages of seven and eighteen, especially in boys, and is caused by
the same forms of violence as produce Colles' fracture.

Although clinically the appearances in these two injuries bear a
general resemblance to one another, separation of the epiphysis may
usually be identified by the directly transverse line of the dorsal
and palmar projections, the folding of the skin observed in the palmar
depression, the absence of abduction of the hand and the ease with
which muffled crepitus can be elicited (E. H. Bennett). The deformity
is readily reduced, and the fragments are easily retained in position.

This injury is often complicated with fracture of the shaft or styloid
process of the ulna, or with dislocation of the radio-ulnar joint, and
it is not infrequently compound, the lower end of the shaft being
driven through the skin on the palmar aspect immediately above the
wrist. Impairment of growth in the radius seldom occurs; when it does,
it results in a valgus condition of the hand (Fig. 48), calling for
resection of the lower end of the ulna.

[Illustration: FIG. 48.--Manus Valga following separation of lower
radial epiphysis in childhood.

(Mr. H. Wade's case.)]

The _treatment_ is the same as for Colles' fracture.

#Fracture of the Lower End of the Ulna.#--The lower end of the _shaft_
of the ulna is seldom fractured alone. The _styloid process_, as has
already been pointed out, is frequently broken in association with
Colles' and other fractures of the lower end of the radius.

Separation of the _lower epiphysis_ of the ulna sometim