528 DISEASES OF THE ORGANS OF LOCOMOTION. 



be somewhat stronger in robust, full-blooded persons than in those 

 who are weak and anaemic. 



Among the inducing causes of acute articular rheumatism the more 

 important are temporary exposure to cold, either by suddenly wet- 

 ting the heated body, or by being subjected to a draught, and con- 

 tinued residence hi damp dwellings and working in damp places. The 

 working-classes, who are chiefly exposed to these bad influences, are 

 consequently more subject to the disease than the well-to-do classes. 

 In most cases the exciting cause cannot be recognized. The disease 

 occurs all over the world, but is more frequent in the temperate zones 

 than in the polar regions or the tropics. At some times, particularly 

 during the winter and spring, the disease is so common that the num- 

 ber of cases reminds us of an epidemic. In summer and autumn the 

 cases are usually solitary. 



ANATOMICAL APPEARANCES. We do not often have the oppor- 

 tunity of examining the bodies of persons who have died during an 

 attack of acute articular rheumatism. When we do, the changes 

 found in the joints are often unimportant, being limited to a moder- 

 ate hypersemia of the synovial capsule and a slight increase and tur- 

 bidity of the synovia. In some cases even these do not remain to tell 

 of the inflammation that has undoubtedly existed during life, and the 

 result of the autopsy is almost as negative as in most cases of erysipe- 

 latous dermatitis. On the other hand, on post-mortem examination, 

 we occasionally find the synovial capsule of some joints of a dark-red 

 color, from hyperaemia and ecchymosis, relaxed and puffed up, the joint 

 dilated and filled with purulent fluid ; the ends of the neighboring bones 

 even may be injected and contain extravasations of blood. In all recent 

 cases the blood contained in the heart and large blood-vessels shows 

 very plentiful deposits of fibrin. There are also the frequent anatom- 

 ical changes due to the complications of articular rheumatism, par- 

 ticularly of pericarditis, endocarditis, and myocarditis. 



SYMPTOMS AND COURSE. In some cases the outbreak of the dis- 

 ease is preceded for a few days by general uneasiness and a feeling of 

 weariness in the limbs. In others, the premonitory symptoms are 

 wanting, and the attack begins suddenly and unexpectedly. The 

 onset of the disease is not frequently marked by a chill, as we have 

 learned is the case in pneumonia and some other inflammatory dis- 

 eases. Usually there is only a slight rigor, which is often repeated 

 during the first few days ; in the other cases even this is absent, and 

 there is from the first the hot feeling, which otherwise does not occur 

 till after the chill. Just as the symptoms of fever begin, or soon after- 

 ward, the patients complain of pain in one or usually in several joints ; 

 this is moderate at first, but quickly and steadily becomes more severe 



