CHRONIC POLYARTHRITIS 55 



In the early stages, during the exacerbations of lame- 

 ness, there is a slight rise in temperature. The diagnosis 

 must exclude osteoporosis more than anything else. This 

 is done by noting that the bony enlargement is confined 

 wholly to the articulations, while in cases of osteoporosis 

 the shafts of long bones, the flat bones, and the axial skel- 

 eton generally, are involved. The entire course of chronic 

 polyarthritis in horses requires several years to exhaust 

 itself. The prognosis is invariably unfavorable. 



Treatment. In the early stages I have seen some good 

 results from treatment aimed at the supposedly infec- 

 tious character of the trouble, such as bacterin therapy 

 with strepto-bacterins and staphylo-bacterins, and the 

 administration of such remedies as salol, hexamethyl- 

 enamin, and arsenic. Locally, active counter-irritants are 

 employed. "When marked changes have occurred in and 

 around several articulations, not much remains to be 

 done. 



Relief from lameness can be obtained for short periods 

 of time in the latter cases by the administration of a 

 mixture containing potassium iodid, phytolacca and col- \ 

 chicum seed three times daily for a week or ten days. The ^ 

 enlarged and deformed articulations are to be massaged 

 with oily preparations of iodin, or with mild mercurial 

 ointments. 



The use of the actual cautery with the object of cor- 

 recting the joint lesions and overcoming existing lameness 

 is in these cases insupportable. 



The joints most commonly affected are the pastern, the 

 ankle, the hock, the stifle, and the carpus. The elbow 

 and shoulder joints are rarely involved. In a few cases 

 I have even seen involvement of the tempero-maxillary 

 articulation. 



From the good results derived in the early stages of 

 some cases with the use of bacterins, it is fair to assume 



