PICKED-UP NAILS, Etc. (“GATHERED NAIL.”)
Penetrating wounds of the plantar region are, as in the horse, usually included under the heading of “Picked-up Nails.” They are only seen in oxen or cows which are not shod. Pointed objects, like nails, harrow teeth, sharp fragments of wood or glass, etc., may produce injuries of the character of that now in question.
In considering the position of such wounds we may for convenience divide the plantar region into two zones, one extending from the toe of the claw to the point of insertion of the perforans tendon, the other comprising the region between this insertion and the bulb of the heel.
Symptoms. Lameness occurs immediately, and varies with the intensity of the existing pain. If the offending body has not remained fixed in the wound, this lameness may in a few moments disappear, either for good or merely for a time. The recurrence of lameness on the following day or a couple of days later marks the commencement of inflammatory changes in the deeper seated tissues. This lameness in many instances is accompanied by a movement suggestive of stringhalt, the foot being kept on the ground only for a very short time, or sometimes not being brought into contact with the ground at all.
The depth to which the offending object has penetrated, and the direction it has taken, may sometimes be discovered by a mere casual examination of the sole. In other cases only the orifice by which it has penetrated can be found. If the injury has existed for several days, the discharge from the puncture will be thin and blackish, purulent, or blood-stained, according to the case. Fever and general systemic disturbance suggest an injury of a grave character.
Diagnosis. The diagnosis is easy, inasmuch as the lameness almost directs examination to the foot.
Prognosis is rarely grave. The direction, the situation and mode of insertion of the flexor tendon, which forms the plantar aponeurosis, ensure this aponeurosis being rarely injured by objects penetrating from without. The points of the offending bodies usually pass either forwards to the phalanx or backwards in the direction of the plantar cushion.
Treatment. The first stage in treatment consists in removing the foreign body and thoroughly thinning the neighbouring horn. An antiseptic poultice consisting of linseed meal saturated with 3 per cent. carbolic acid or creolin solution is then applied. Considerable and progressive improvement usually takes place in a few hours. If lameness persists, surgical interference becomes necessary; in the anterior zone it is confined to removing any dead portions of the velvety tissue and to extirpating the fragment of bone which has undergone necrosis. In the posterior zone the sinus must be probed and laid open, so that all the diseased parts can be treated as an open wound.
If, as happens in exceptional cases, the plantar aponeurosis is found to be severely injured, the complete operation for picked-up nail, as practised in the horse, may be performed, or the claw may be amputated. In the former operation the horn covering the sole is first thinned “to the blood.”
The stages of operation are as follows:—