ns have been known to induce attacks, and sometimes to abort
them or even to cause their disappearance. Hence it has been recommended
that treatment by suggestion should be employed along with tonic doses
of quinine and arsenic.

HYSTERICAL OR MIMETIC JOINT AFFECTIONS

Under this heading, Sir Benjamin Brodie, in 1822, described an affection
of joints, characterised by the prominence of subjective symptoms and
the absence of pathological changes. Although most frequently met with
in young women with an impressionable nervous system, and especially
among those in good social circumstances, it occurs occasionally in men.
The onset may be referred to injury or exposure to cold, or may be
associated with some disturbance of the emotions or of the generative
organs; or the condition may be an involuntary imitation of the symptoms
of organic joint disease presented by a relative or friend.

It is characteristic that the symptoms develop abruptly without
satisfactory cause, that they are exaggerated and wanting in harmony
with one another, and that they do not correspond with the features of
any of the known forms of organic disease. In some cases the only
complaint is of severe pain; more often this is associated with
excessive tenderness and with impairment of the functions of the joint.
On examination the joint presents a normal appearance, but the skin
over it is remarkably sensitive. A light touch is more likely to excite
pain than deep and firm pressure. Stiffness is a variable feature--in
some cases amounting to absolute rigidity, so that no ordinary force
will elicit movement. It is characteristic of this, as of other
neuroses, that the symptoms come and go without sufficient cause. When
the patient's attention is diverted, the pain and stiffness may
disappear. There is no actual swelling of the joint, although there may
be an appearance of this from wasting of the muscles above and below. If
the joint is kept rigid for long periods, secondary contracture may
occur--in the knee with flexion, in the hip with flexion and adduction.

The _diagnosis_ is often a matter of considerable difficulty, and the
condition is liable to be mistaken for such organic lesions as a
tuberculous or pyogenic focus in the bone close to the joint.

The greatest difficulty is met with in the knee and hip, where the
condition may closely simulate tuberculous disease. The use of the
Rontgen rays, or examination of the joint under anaesthesi