n of the lymph glands of the limb is exceptional,
but may follow upon infection of the skin around the orifice of a sinus.

A slight rise of temperature in the evening may be induced in quiescent
joint lesions by injury or by movement of the joint under anaesthesia, or
by the fatigue of a railway journey. When sinuses have formed and become
infected with pyogenic bacteria, there may be a diurnal variation in the
temperature of the type known as hectic fever (Fig. 11).

_Relative Frequency of Tuberculous Disease in Different
Joints._--Hospital statistics show that joints are affected in the
following order of frequency: Spine, knee, hip, ankle and tarsus, elbow,
wrist, shoulder. The hip and spine are most often affected in childhood
and youth, the shoulder and wrist in adults; the knee, ankle, and elbow
show little age preference.

_Clinical Variations of Tuberculous Joint Disease._--The above
description applies to tuberculous joint disease in general; it must be
modified to include special manifestations or varieties.

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