DISEASES OF THE HORSE'S FOOT 345 



however, much of what can really be urged against it dis- 

 appears, and on farms and other places where a skilled and 

 competent dressing of an operation wound cannot be looked 

 for, it is sometimes wise to advise this method of treatment 

 in preference to more advanced methods of operating. So 

 far as we can judge, the after-effects are very little worse 

 than those following other operative measures, more 

 especially when a suitable case has been chosen. 



This method of treatment is particularly applicable to 

 cases of chronic sub-horny quittor in the more posterior 

 parts of the foot. Here, if one or more fistulas exist, their 

 openings are probed and the direction of the sinuses deter- 

 mined. In all probability they are burrowing down along- 

 side the wall to the sole, where, for want of outlet, they are 

 invading the substance of the plantar cushion or the plantar 

 aponeurosis. 



Should this preliminary probing demonstrate that neither 

 of the fistulas run dangerously near the joint, then the 

 operation may be decided on. 



The animal is cast and chloroformed, the foot firmly 

 fixed, and the horn of the quarter rasped away quite thin. 

 The sole of the same is also pared with the knife until 

 the horn of both the quarter and the sole yields easily to 

 pressure of the thumb. All that is then needed is three or 

 four long, round, and pointed irons (about £ to f inch in 

 diameter) heated to redness. These are inserted into the 

 fistulas, and the false mucous coat of these passages thus 

 destroyed. When the iron, on being directed into the 

 fistulous opening at the coronet, is found to travel alongside 

 the wall, and to easily reach the sole, it should be made to 

 go further still. The sole is penetrated, and a dependent 

 opening thus made for the escape of the discharge that 

 afterwards accumulates. 



What happens now, of course, is that an intense and 

 ^ute inflammation is set up along the whole track of the 

 fistula, in which position the inflammatory changes were 

 heretofore chronic. The whole lining of the fistula, and 

 with it, we hope, all necrotic tissue, is cast as a slough, 



