54 SPECIAL EQUINE THERAPY 



CHRONIC POLYARTHRITIS 



Chronic inflammatory processes involving more than 

 one articulation at the same time occur vsdth fair fre- 

 quency in horses. The condition is most often seen in 

 horses past eight years of age, but younger horses are 

 not entirely exempt. The etiology is not always the same, 

 and in many instances this cannot be ascertained. By far 

 the greatest number of these cases are the result of acute 

 polyarthritis that developed at an earlier period of the 

 animal's existence as sequelas to infectious diseases. In- 

 fluenza, complicated strangles, pneumonia and pleurisy 

 can be named as examples of predisposing affections. 

 Some cases are, no doubt, due to a rheumatic diathesis, 

 and are precipitated as the result of unhygienic sur- 

 roundings, insufScient nutriment, and excessive work. 

 The process is always non-suppurative, and is character- 

 ized by a tendency towards malformation by the develop- 

 ment of osseous changes, ligamentous and tendinous 

 thickenings, and subsequent muscular atrophy. 



There are in this condition periodic axacerbations of 

 lameness. Between these periods the horse is merely 

 "sore." This "soreness" is peculiar in the fact that it 

 disappears to a great extent, temporarily, with exercise. 

 The changes in the joints, consisting of enlargement 

 chiefly, begin to appear at the end of several months. 

 With their appearance comes permanent lameness. Sev^ 

 eral months, at times a year, later wasting of the mus- 

 cular frame in the affected limbs begins. The horse event- 

 ually becomes "out of condition" generally, tires easily, 

 refuses its feed after strenuous exercise or work, and 

 finally is wholly unserviceable. In this stage most of 

 these horses rarely lie down; when they do at times 

 assume the recumbent position, they require some assist- 

 ance in getting up. 



