Before you consent to operate upon any animal, examine the feet. If the hoof is weak or even weakly, refuse at once. If the hoof be strong and thick, the wall upright, and the frog small, you may consent, with the best hopes of success. Have such a horse put into the stable, and the diseased foot or feet kept wet for a week prior to the operation. This frequently has the effect of constringing the arteries, greatly depriving the part of blood. That result renders the use of the knife more cleanly and more easy. Two days prior to the important one have the hair cut short over the place or places where you design to make your incisions. By so doing, all chance of hair getting into and irritating the wound will be effectually destroyed. This may happen, and, should the hair be left on, much delay will be occasioned, while the animal's sufferings must be augmented if the hair be clipped after the horse is down for operation.
THE MODE OF FASTENING BACK THE SIDE
OF A PERPENDICULAR WOUND.
Never operate upon a horse with the hair uncut—leave that to parties who league with the lowest class of horse-cheats. Cut off hair two days beforehand. Make an incision through the skin about three-quarters to one inch long. Have a needle and thread ready—a strong surgeon's needle and a stout twine. Pierce the divided skin from the inside to the outside, leaving a moderate piece of twine hanging out of the wound. Carry the twine under the leg, and pierce the integument on the other margin of the wound—also from the interior to the exterior. Then bring the piece of twine left hanging out of the first puncture and the needle together, at the back of the leg. Slightly tighten the twine; fasten these two ends in a bow, and the effect will be to keep the sides of the incision asunder.
If you design to perform the high operation, choose a spot a little above the pastern, and incise the skin at one cut, if possible. The high operation is most approved of for general purposes, and, as before remarked, destroys sensation in the entire hoof. Some proprietors think it well to leave a little feeling in the forward portion of the foot, which is free from disease. This is done to escape those results that have already been enumerated as the effects of total insensibility. The high operation is, therefore, performed only on one side, and the posterior or low division on the other. There are two spots at which the low operation may be accomplished. The author has given the reader a representation of the anatomy of the leg. He presents a view on page 455, of the places where the incisions can be made.
Either of the lower operations, regarded by itself, is very uncertain in its effect; and, if taken both together, they present no advantage over the superior opening.
These remarks may be better comprehended, by comparing this engraving with the course of the nerve shown in the previous illustration.
When the skin is divided—supposing the horse is neurotomized for the first time—nothing is visible but white-looking cellular tissue. This must be carefully dissected away with a pair of forceps and a scalpel. Dissect on until the nerve and artery are exposed plainly to view. Then take a crooked needle and thread. Pierce the nerve—this you may do fearlessly. The author has not known it to produce pain. The fibers composing the nerve are so fine that the needle's point is blunt when compared with them. It, therefore, glides through them without pricking any of the filaments.
The superior opening represents the place where one side of the foot may be deprived of sensation by a single division.