Diseases of the Horse's Foot

by H. Caulton Reeks

At other times the prick is not so readily apparent. The nail or other object has penetrated and afterwards withdrawn itself. The natural elasticity of the horn, especially that of the frog, causes it to contract upon the puncture, and to largely obliterate the hole made. What, therefore, may look to be but a simple injury to the horn alone may in reality be the only evidence of a stab complicating the sensitive structures. It thus behoves the veterinary surgeon to follow up and carefully cut out any unnatural-looking mark in the horn, more especially if the horn is discoloured, or if blood is extravasated into its fibres, or there is moisture exuding from the part.

In some cases of this description the knife in the act of paring comes into contact with the cause of the trouble. Sometimes this is a nail, sometimes a sharp and small piece of flint, so deeply penetrated as to have become quite buried. When met with in this manner, however, the foreign body is more often than not a splinter of wood deeply embedded in the cleft of the frog or in the frog itself.

The fact that multiple punctures may occur should here be remembered, and the remainder of the inferior surface of the foot thinly pared.

On withdrawal of the foreign object blood may immediately follow. Should the former have been fixed in position for some time, however, pus is nearly always found at the bottom of the wound. As a rule, its removal is comparatively easy, but one case recalls itself to the author's mind in which the extraction was a matter of considerable difficulty. The offending object was a large, flat-headed nail, some 2 inches long. This was driven fast into the os pedis, and necessitated the employment of a pair of pincers and the exertion of some amount of force to move it from its position.

In this connection it must be remembered that the penetrating object sometimes breaks off after entering the foot. The fact that this occasionally happens only serves to give point to the advice we have previously rendered—that every stab should be carefully probed, and its exact condition and depth ascertained.

In those cases where percussion has led to the positive opinion that pus really exists, then the exploration must be most searching. There may, or may not, be a suspicious-looking mark to work on. In the latter case, the veterinary surgeon must not be content with confining his paring operations to one spot. The sole should be carefully thinned all round, and the thinning cautiously proceeded with until either small, pin-point hæmorrhages denote that healthy sensitive structures have been reached, or a sudden flow of pus indicates that the injury has been definitely located.

While the symptoms remain much about the same, the diagnosis of pricks received in the forge, as compared with those occurring in the natural manner, is easy. The animal starts to the forge quite sound, and returns, perhaps, with a slight limp. The slight limp in two days' time becomes a decided lameness, and no doubt remains as to what has occurred. The mere fact of the lameness arising immediately after a visit to the forge should be sufficient in the majority of cases to lead one to a correct diagnosis.

Where the opinion has been formed that a prick has been received, then the shoe should be removed.

This operation should always be superintended by the veterinary surgeon himself. After the removal of the clinches, the nails should be drawn one at a time with the pincers, and carefully examined. Often the offending nail may thus be picked out by observing upon it blood-stains, or the moisture from inflammatory exudate or from pus. Further inflammation will also be gathered by occasionally meeting with a nail that has split.

At this stage, too, the veterinary surgeon should have noticed whether or not the smith has previously sent the animal home with what is known as a 'draw back.' He has discovered, immediately after he has done it, that he has pricked the animal. He has then withdrawn the nail, and either sent the animal back with that nail altogether missing from the set in the shoe, or with the hole filled up with a stump.