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recourse is to amputation.

#Gun-shot injuries# of joints vary in severity from a mere puncture of
the synovial layer by a chip of shell to complete shattering of the
articular surfaces. Between these extremes are cases in which the
capsular and synovial layer are extensively lacerated without
involvement of the bones, and others in which the bones are implicated
without serious damage being done to ligaments or synovial layer--for
example, by a bullet passing through and through the cancellated part
of one of the constituent bones, or by a fissure extending into the
articular surface.

In all degrees the great risk is from septic infection, which may be
assumed to be present in all but the last-named variety.

The _treatment_ consists in immediately cleansing the wound by
excising grossly damaged tissue and removing any foreign body that may
have lodged; disinfecting the exposed part of the joint cavity with
eusol, "bipp," or other antiseptic, and closing the wound or
establishing drainage, according to circumstances. The joint is then
immobilised till the wound has healed, after which massage and
movement are commenced. When the bones are shattered or when sepsis
gets the upper hand and disorganises the joint, amputation is called
for.

#Sprains.#--A sprain results from a stretching or twisting form of
violence which causes the joint to move beyond its physiological
limits, or in some direction for which it is not structurally adapted.
The main incidence of the force therefore falls upon the ligaments,
which are suddenly stretched or torn. The synovial layer also is torn,
and the joint becomes filled with blood and synovial fluid.

Muscles and tendons passing over the joint are stretched or torn, and
their sheaths filled with serous effusion. It is not uncommon for
portions of bone to be torn off at the site of attachment of strong
ligamentous bands or tendons, constituting a "sprain fracture"; or for
intra-articular cartilages to be torn and displaced, as in the knee.

_Clinical Features._--The injury is accompanied by intense sickening
pain, and this may persist for a considerable time. At first it is
aggravated by moving the joint, but if the movement is continued it
tends to pass off. The particular ligaments involved may be recognised
by the tenderness which is elicited on making pressure over them, or
by putting them on the stretch. In this way a sprain may often be
diagnosed from a fracture in which t