In conclusion, we may say that the operation is one of some delicacy, and needs a good surgeon for its successful performance. Furthermore, no one of the antiseptic precautions we have advised can be omitted. It is, perhaps, these two considerations (and in justice to the English surgeon we should say most probably the latter of them) that have prevented this operation from being generally adopted.
That it is successful there is no gainsaying. Professor Bayer, of the Vienna School, with whose name is associated the last of the three methods of operating we have described, is enthusiastic in praise of the operation, and says: 'The favourable results that I have got by this operation have caused me wholly to abandon the medicinal treatment, and to prefer in all cases the surgical operation as being the best means to the end.'
Partial Excision of the Lateral Cartilage.—Discarding the somewhat elaborate methods we have just described, there are English operators who removed the necrosed portion only of the cartilage, and do so in what appears at first sight a comparatively rough-and-ready manner.
The apparent roughness is that they do not concern themselves with conserving the coronary cushion, and hesitate but little in cutting portions of it bodily away. One would imagine that in this case the quarter of the side operated on would be always more or less bare of horn. Such, however, is not the case.
To perform this operation the animal is again cast and chloroformed. Some operators, however, use the stocks and dispense with the anæsthetic. The foot is first well cleaned with soap and water and a stiff brush, and the hair of the coronet over the seat of operation shaved. Again, too, the horn of the affected quarter is rasped until it yields easily to pressure of the thumb, and the whole of the foot washed in an antiseptic solution.
A probe is now inserted into the opening at the coronet, and the direction of the fistula noted, after which the foot is firmly secured, and an Esmarch bandage and tourniquet applied to the limb.
This done, a triangular or wedge-shaped portion of skin, coronary cushion, and thinned horn is removed with a strong sage-knife or scalpel.
The base of the wedge-shaped portion removed contains the opening of the fistula, and the apex of the wedge should reach to the bottom of the sinus (see Fig. 142).
After the horn is removed and the fistula followed up, it is sometimes found that what we at first thought was its end, it may now be continued in an altogether different direction.
It is again followed up with the probe, and the horn and sensitive structures excised until we are quite certain we have reached its furthest extent.