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 haemorrhages 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  He has then withdrawn the nail, and either sent the animal back with that nail altogether missing from the set in the shoe, or with the hole filled up with a stump.

The shoe once off, the holes made by the nails in the horn should be minutely examined for the presence of haemorrhage, inflammatory fluid, or pus exuding from them, and also for evidence of their correct placing in the foot.  Should fluid matter issue from any one of them, or should it be deemed that one has approached too near the inner margin of the white line, more especially if tenderness exists around it, that hole should be followed up with a ‘searcher’ or small drawing-knife until diagnosis is certain.

Complications.—­Before proceeding to discuss the complications that may arise in the case of pricked foot, we may call to mind that the anatomy of the parts teaches us that the most serious position in which a punctured wound can occur is at the centre of the foot.  Here the plantar aponeurosis, the navicular bursa, the navicular bone itself, or the pedal articulation may be injured.