SURGICAL OPERATIONS. 259 



and with it incises the enlargement, sending the blade right through 

 the periosteum, and also through the substance of the exostosis, if 

 it be not too solid for the knife to penetrate. This latter fact is 

 only to be ascertained by actual experience, and no opinion formed 

 after an external examination can be of any value, such being muoh 

 more the guess of a pretender than the judgment of a surgeon. 

 The age of the animal may be some guide, but even this it is 

 better not to depend upon too entirely. It is true that young 

 horses freely cast forth exostoses, which aged animals mostly 

 absorb; but this rule, though very general, has exceptions, and 

 by no means is to be absolutely depended upon. 



The enlargement being cut through, next take a seton-needle, 

 armed with a tape, and draw it through the channel already made. 

 Tie a knot at either end of the tape, large enough to prevent its 

 being pulled through the opening at either end, and the business 

 is over. The affair is very simple, and the horse may be at once 

 let up. It is, however, in some cases, and only in some, of so much 

 benefit that the horse, being thrown ' dead lame/ gets up and trots 

 off quite sound. However, ere you adopt the operation, apprise 

 the owner of the risk incurred, and that it is by no means a cer- 

 tain cure. Leave the choice with him, but be sure and tell him 

 the opening made for the entrance and exit of the seton com- 

 monly leave a blemish behind them ; and where the seton trav- 

 eled, often there remains a thickening, which it may require months 

 to obliterate. 



The after part of the treatment consists in merely having the 

 seton daily moved to and fro, though some persons apply an active 

 blister all over the parts immediately in the neighborhood of the 

 seton, under the idea that the vesicatory renders the operation of 

 greater efficacy, which, however, is very questionable. When pe- 

 riosteotomy acts at all, it mostly does so at once ; and when it» 

 benefits are not immediate, it is better to withdraw the seton, to 

 prevent after-blemish, rather than hazard further and useless treat- 

 ment by the application of a stimulant to skin already deprived 

 of any connection with the deeper-seated structures. 



Division of the Flexoe Tendon. 



There are so many accidents and diseases that may produce 

 contraction of the flexor tendons, that we only wonder we do not 



