GENERAL DISEASES. 101 



RHEUMATISM. 



Varieties. — Acute, Chronic, and Muscular Eheumatism. 



ACUTE RHEUMATISM.— Definition.— Is a constitu- 

 tional fever characterized by the special tendency to inflam- 

 mation of certain structures, viz. : the articulations, the 

 coverings of the tendons and muscles, the pericardium and 

 endocardium. These inflammations have a tendency to dis- 

 appear from one part and to reappear in another, and are 

 called metastatic. 



Nature of the Disease. — Rheumatism is a general disease, 

 the proximate cause of which has been maintained to be a 

 poisonous substance circulating in the blood. This poison 

 is stated to be lactic, or some other acid. No excess, how- 

 ever, of any such acid has yet been detected in the blood. 



Etiolog^y. — JExcifhig causes of rheumatism are : exposure 

 to cold and wet, sudden chills, damp and malhygienic 

 conditions. Predisposing causes : a constitutional tendency 

 to rheumatism, or ' rheumatic diathesis,' as it is termed. 



Symptoms. — The local symptoms may be preceded by 

 febrile disturbance. 



There is sudden and severe lameness, with or without 

 swelling of one or more joints, most commonly the stifle 

 and fetlock, less commonly of the hock and knee. On 

 manipulation the afl'ected joints are found to be excessively 

 tender. The joints may be afl'ected in pairs — for example, 

 the two hock joints or the two stifles may be simultaneously 

 involved, and the lameness is thus symmetrical. The tem- 

 perature is elevated, and may reach as high as 104°-106° F. 

 The pulse is accelerated, firm, and full ; the urine is high- 

 coloured, scanty, acid or neutral in reaction, and loaded with 

 hippurates and hippuric acid ; the bowels are constipated. 



In most acute cases the heart is afl'ected. If the inflam- 



