PART VII. 



DISEASES OF THE ORGANS OF LOCOMOTION. 



CHAPTER I. 



ARTICULAR RHEUMATISM. POLYARTHRITIS 

 RHEUMATICA. 



Definition.— Articular rheumatism is evidently an infectious 

 febrile disease in which several joints are affected. It is a 

 serous or serofibrinous inflammation of the joints. It may 

 suddenly shift from one joint to another. 



Etiology.— The actual cause of the disease has never been 

 definitely proved, but all indications point to infection. 

 Several factors no doubt have considerable influence in 

 bringing on the attacks, such as (a) subjection to cold and 

 chilling the surface of the body; (b) keeping animals in cold, 

 damp cellars, or forcing them to sleep out in extreme cold 

 weather; (c) infection following birth of the young. The 

 close association of the disease with endocarditis and other 

 diseases of serous membranes further suggest its infectious 

 nature. 



Pathology.— The joint capsule is more or less distended 

 with a yellowish gelatinous-like fluid mixed with the synovia. 

 The connective tissue is infiltrated with the same material. 

 Examination of the synovial membrane itself reveals swelling, 

 injection and hemorrhages. The cartilage of the joint is 

 bluish or yellow in color and the surface roughened. Chronic 

 cases show marked thickening of the periarticular tissue. 

 Similar changes are often found in the tendon sheaths. The 

 musculature shows atrophy. 



