cause enlargement of the bone or to be discernible in a skiagram.

#The formation of peri-articular abscess# takes place in rather more
than fifty per cent. of cases. When left to themselves, such abscesses
tend to spread up the thigh, or down the back of the leg between the
superficial and deep layers of calf muscles, and numerous sinuses may
result from their rupture through the skin.

#Attitudes of the Limb in Knee-Joint Disease.#--The attitude most
often assumed is that of _flexion_, with or without _eversion of the
leg and foot_. The flexion is explained by its being the resting
attitude of the joint, and that which affords most ease and comfort to
the patient. Once the joint is flexed, the involuntary contraction of
the flexor muscles maintains the attitude, and if the patient is able
to use the limb in walking, the weight of the body is a powerful
factor in increasing it. The eversion of the leg is probably
associated with contraction of the biceps muscle. _Backward
displacement of the tibia_ is met with chiefly in neglected cases of
chronic disease of the knee when the child has walked on the limb
after it has become flexed.

In certain cases, _genu valgum_ or abduction of the leg is present
along with a slight degree of flexion. The valgus attitude is
associated with slight lateral displacement of the patella, with
prominence and apparent enlargement of the medial condyle, with
depression of the pelvis on the diseased side and apparent lengthening
of the limb.

#Treatment of Tuberculous Disease of the Knee.#--Conservative measures
are always indicated in the first instance, and are persevered with so
long as there is a prospect of obtaining a movable joint.

_Conservative Treatment._--If the joint is sensitive and tends to be
flexed, the patient is confined to bed, the limb is secured to a
posterior splint, and extension with weight and pulley persevered with
until these symptoms have disappeared; during this time, from three to
six weeks, methods of inducing hyperaemia and other anti-tuberculous
procedures are employed. If it is proposed to inject iodoform or other
drug, the needle is inserted into the interval between the bones on
the medial side of the ligamentum patellae or into the upper pouch when
this is distended with fluid.

If there is no pain or tendency to flexion, or when these have been
overcome, the limb is put up in a Thomas' splint (Fig. 125) and the
patient allowed to go about. The sp