Causes. - Seeing that this accident to, and consequent severe wounding of, the keratogenous membrane nearly always occurs in but one way, it is worthy of special mention. So far as we are able to ascertain, it is an accident peculiar to horses continually engaged in shunting operations either in pits or station-yards. At the moment the animal is released from the waggon he has been pulling, and should turn to the right or the left in order to allow it to pass him, the shoe either becomes wedged in between two converging rails, or is trapped by the wheel of the waggon. Either the approaching waggon with the added weight its impetus gives it then pushes the animal suddenly away, leaving a part of his foot still fixed to the rails, or the animal himself, feeling securely held, makes a sudden effort to release himself, and draws his foot cleanly out of the imprisoned horny box.
The author calls to mind a case in which entire removal of the horn of the foot of an ox occurred through the passing over it of the wheel of a heavily-laden cart. It is therefore quite conceivable that the same accident might occur to the horse. As a matter of fact, we find one case on record where one-half of the horny box was thus removed.[A]
[Footnote A: Veterinary Record, vol. xiii., p. 129.]
So far as we are able to gather, it is more a result of imprisonment of the shoe than of the foot. It appears, further, to be always a result of the animal being newly shod, and the clinches firmly secured; so much so that it would be probable, with imperfectly secured clinches, that the animal would draw the hoof from the clinches and the shoe rather than the foot from its horny covering.
Therefore, as the author of one of the cases we shall afterwards relate suggests, it should be proposed as a preventive that the shoe-nails of animals regularly engaged in work on the metals should not be clinched in the regulation manner, but should have their points merely screwed off, and the nails afterwards rasped level with the wall.
These cases are particularly interesting as illustrating the rapid manner in which a new hoof is afterwards formed, and the way in which the exposed sensitive laminae take their share in adding to, though not forming the bulk of, the horn of the wall.
From the cases we are able to record it will be seen that this accident need not be looked upon as fatal, nor the injury itself beyond hope of repair. Dependent largely upon the temperament of the animal, the amount of pain that is caused, and the way in which the animal bears it, recovery may be looked for. Even from the very commencement of the accident, however, the pain may be so acute and the animal so violent with it that slaughter becomes necessary.
Treatment. - This consists in applying an antiseptic and sedative dressing to the injured parts (for example, Carbolized Oil and Tincture of Opium, equal parts) and afterwards bandaging.
From the only data we are able to work on, it appears that this dressing should be repeated daily, the bandage being removed, each time, the foot well bathed in warm water, and the dressing and bandage afterwards replaced. On first sight, it would appear that once cleansed and bandaged the dressings might be left in situ for several days. Seeing, however, that suppuration, if once set up, would add further to the intense pain the animal is already suffering, and considering the always constant exposure of the foot to infection, it is perhaps wise to persist in daily changing of the dressings.
At the same time, the general health of the animal should be attended to. Suitable febrifuges should be administered, either in the shape of a dose of physic, or salines and liq. ammonia. acetatis; and the pain, if appearing unbearable, allayed by doses of choral and hypodermic injections of morphia.
Recorded Cases. - 1. 'A short time ago I was called to see a horse which had had his hoof torn off in a railway "point." When I arrived at the stable the injury had been done two hours, and the horse had been led from the railway to a loose-box nearly half-a-mile off. On going to this box I was surprised and horrified to find the poor animal mad with pain, rolling and dashing himself about. When on his back he would struggle and kick the walls with the injured foot, as though unconscious of pain. Not one moment was he still, and as I could see that the sensitive structures were much damaged by his violence, I obtained a gun and put him out of his pain.
'The accident happened in this way. The horse was employed in shunting coal-waggons, and had just drawn four loaded trucks up to a point at which they diverged to the left, and the horse, being unhooked, ought to have turned to the right. Here, unfortunately, the near fore-foot became wedged in between two converging railway plates, one of which formed a part of the waggon-way, on which the trucks were running. The horse was a big animal, and freshly shod with heavy shoes, on which a toe-piece and calkins were used. The shoe was roughly but strongly nailed on with eight nails, the clinches of which were all firm. This shoe was fitted wide at the heels, and when the foot was fixed in the points (toe downwards) it protruded over the face of the rail. When the trucks reached it they pressed it down, and, the horse leaning forward, the hoof was drawn off like a glove. The hoof was almost as clean inside as if taken off by maceration - only towards the toe was a small portion of the coffin-bone and some torn laminae left inside the hoof.
'As soon as possible after the accident, so I was told, the foot was bound up with tow and a bandage; then a sack was cut up and placed over all, and the horse slowly led to his loose-box. He "carried" the leg all the way, limping along on the three sound ones. Almost immediately after reaching the box he lay down, but only for a short time. The standing position was not long maintained - profuse perspiration set in, and the alternations of position became more rapid and violent, till plunging and rolling were added to the other signs of excruciating pain. I was also told that the groaning of the poor animal was almost constant, and at times so loud and prolonged as to amount to a shriek.
'I have no experience of a similar case, and I should not have supposed that this accident would have caused such acute suffering and violent symptoms. I think I have heard of such cases making a complete recovery; but I feel sure that, in this case, I only anticipated death by, at most, a few hours.'[A]
[Footnote A: Veterinary Record, vol. iv., p. 127.]