DISEASES OF THE MUSCLES. 



Muscular Rheumatism. 



(Muscular Pains, Rhcuniatismus Musculoruw.) 



Muscular rheumatism is a primary affection with more or less 

 complication of the muscular system. In some cases there is little or no 

 inflammation present, no fever, and the only indication of rheumatism 

 being present is stiffness of gait and pain on pressure; it may occur as 

 acute, subacute, and chronic. 



Etiology. — The cause of rheumatism, which has been described as 

 a certain poisonous substance, may also be due to cold, atmospheric 

 influences, etc., or dampness, animals lying in kennels that do not get 

 the sun, or being kept in the cellar, particularly with asphalt floors 

 hunting dogs becoming wet, and after great exertion, sleeping with wet 

 coats. We have, undoubtedly, a number of diseases of the muscular 

 system which do not develop from rheumatism — for instance, abnormal 

 muscular exertion and consequent laceration of some of the muscular 

 fibres — also from disturbances of the circulation, from chronic toxic 

 influences, etc., from some infectious agent as in acute articular rheuma- 

 tism, certain affections of the spinal cord, also pleuritis, nephritis and 

 other affections. It would be much better to discard the name ''mus- 

 cular rheumatism" and simply call it "muscular pain." Experience 

 has taught the writer that muscular rheumatism is seen frequently in 

 old, delicate, or fat dogs, and is oftener observed in winter than in 

 summer. 



Pathological Anatomy. — It is very difficult to make any definite 

 statement as to the cause of rheumatism. We speak of rheumatic 

 muscular inflammation, but at the same time we do not, as a rule, find 

 any different muscular alterations on post-mortem from animals which 

 have suffered from muscular rheumatism. VCe may find slight altera- 

 tions which have occurred from other causes, such as hyperaemia, slight 

 exudations in the muscles, tendons, and fascia. Deposits occur in the 

 connective tissue (rheumatic callosities). These occur in a man who 

 has suffered for a long time from muscular rheumatism, and in old 

 rheumatic dogs we may also observe characteristic alterations in acute 

 or chronic inflammations and the' connective tissue between the muscular 

 fibres has increased. 



CUnical Symptoms and Course. — Muscular pain is a most marked 

 symptom. This is observed in slight cases by the muscles in an affected 

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