When the main incidence of the infection affects the synovial membrane, the clinical picture may assume the form of a hydrops, or of an empyema in which the joint is filled with pus.  More common than either of these is the well-known white swelling or tumor albus (Wiseman, 1676) which is the clinical manifestation of diffuse thickening of the synovial membrane along with mucoid degeneration of the peri-synovial cellular tissue.  It is well seen in joints which are superficial—­such as the knee, ankle, elbow, and wrist.  The swelling, which is the first and most prominent clinical feature, develops gradually and painlessly, obliterating the bony prominences by filling up the natural hollows.  It appears greater to the eye than is borne out by measurement, being thrown into relief by the wasting of the muscles above and below the joint.  In the early stage the swelling is elastic, doughy, and non-sensitive, and corresponds to the superficial area of the synovial membrane involved, and there is comparatively little complaint on the part of the patient, because the articular surfaces and ligaments are still intact.  There may be a feeling of weight in the limb, and in the case of the knee and ankle the patient tires on walking and drags the leg with more or less of a limp.  Movements of the joint are permitted, but are limited in range.  The disability is increased by use and exertion, but, for a time at least, it improves under rest.

If the disease is not arrested, there follow the symptoms and signs of involvement of the articular surfaces.

Influence of Tuberculous Joint Disease on the General Health.—­Experience shows that the early stages of tuberculous joint disease are compatible with the appearance of good health.  As a rule, however, and especially if there is mixed infection, the health suffers, the appetite is impaired, the patient is easily tired, and there may be some loss of weight.

#Treatment.#—­In addition to the general treatment of tuberculosis, local measures are employed.  These may be described under two heads—­the conservative and the operative.

Conservative treatment is almost always to be employed in the first instance, as by it a larger proportion of cures is obtained with a smaller mortality and with better functional results than by operation.

Treatment by rest implies the immobilisation of the diseased limb until pain and tenderness have disappeared.  The attitude in which the limb is immobilised should be that in which, in the event of subsequent stiffness, it will be most serviceable to the patient.  Immobilisation may be secured by bandages, splints, extension, or other apparatus. Extension with weight and pulley is of value in securing rest, especially in disease of the hip or knee; it eliminates muscular spasm, relieves pain and startings at night, and prevents abnormal attitudes of the limb.  If, when the patient first comes under observation, the limb is in a deformed attitude which does not readily yield to extension, the deformity should be corrected under an anaesthetic.