384 BUREAU OF ANIMAL INDUSTRY. 



established, then the external coat of the articulation proper becomes 

 ulcerated, if it is not already in that state, and we find ourselves in 

 the presence of an ojfenjomt with suppurative synovitis — that is, witli 

 the worst among the conditions of diseased' processes, because of the 

 liabilit}' of the suppuration to become infiltrated into every part of the 

 joint, macerating the ligaments and irritating the cartilages, soon to 

 be succeeded by their ulceration, with the destruction of the articular 

 surface — or the lesion of vlcerative cuiJiritis^ one of the gravest among 

 all the disorders known to the animal econom}-. 



But ulcerative arthritis and suppurative synovitis may be developed 

 otherwise than in connection with open joints; the simplest and 

 apparentlj^ most harmless punctures may prove to be cause sufficient. 

 For example, a horse may be kicked, perhaps, on the inside of the 

 hock; there is a mark and a few drops of blood to indicate the spot; 

 he is put to work, apparently free from pain or lameness, and per- 

 forms his task with his usual ease and facility. But on the following 

 morning the hock is found to be a little swollen and there i«j some stiff- 

 ness. A little later on he betrays a degree of uneasiness in the leg, 

 and shrinks from resting his weight upon it, moving it up and down 

 for relief. The swelling has increased and is increasing, the pain is 

 severe, and, finally, there is an oozing, at the spot where the kick 

 impinged, of an oily liquid mixed with whitish drops of suppuration. 

 The miscliief is done; a simple, harmless, punctured wound has 

 expanded. into a case of ulcerative arthritis and suppurative synovitis. 



Prognosis. — From ever so brief and succinct description of this trau- 

 matism of the articulations, the serious and important chai'acter of 

 these lesions, irrespective of which particular joint is aft'ected, will be 

 readily understood. Yet there will be modifications in the prognosis 

 in different cases, in accordance Avith the peculiarities of structure in 

 the joint specially involved, as for example, it is obvious that a better 

 result may be expected from treatment when but a single joint, with 

 only its plain articular surfaces, is the place of injury, than in one 

 which is composed of several bones, united in a complex formation, as 

 in the knee or hock. As severe a lesion as suppurative synovitis always 

 is, and as frequently fatal as it proves to be, still cases arise in which, 

 the inflammation assuming a modified character and at length subsid- 

 ing, the lesion terminates favorably and leaves the animal with a com- 

 paratively sound and useful joint. There are cases, however, which 

 terminate in no more favorable a result than the union of the bones 

 and occlusion of the joint, to form an anchylosis, which is scarcely a 

 condition to justif}^ a high degree of satisfaction, since it insures a per- 

 manent lameness with very little capacity for usefulness. 



Appreciating now the dangers associated with all wounds of articu- 

 lations, however simple and apparently slight, and how serious and 

 troublesome are the complications which are likely to arise during 



