PERIOSTITIS. 
195 
instrument perforating the tendon fractures the navicular bone, and 
guarantees permanent lameness, if not a fatal synovitis. 
The majority of wounds which we see upon the front of the hoof 
just below the coronet are not deep, neither are they accompanied with 
even a moderate amount of lameness; yet, there are occasionally in¬ 
stances in which the newly sharpened calk will penetrate so deeply as 
to wound the tendon of the extensor pedis at or near the point of its 
attachment upon the pyramidal process of the os pedis, and it is in 
these cases you will see acute and permanent lameness from inflamma¬ 
tion of the wounded tendon which may be accompanied by synovitis, 
periostitis, ostitis, and rarely caries of the pyramidal process. 
There are some horses with the habit of standing with the heel of 
one hind foot resting upon the upper portion of the hoof of the other 
foot, and during the winter months they may keep themselves continu¬ 
ally lame from irritating a previously received wound of the above char¬ 
acter, by their reprehensible practice of standing cross-legged. 
SYMPTOMS AND COURSE. 
All punctured wounds of the foot are not followed by periostitis, 
and usually it is only those in which the wound is extensive, or the peri¬ 
osteum directly injured, that inflammation of this tissue supervenes. If 
the animal is known to have picked up a nail,- the foot is generally al¬ 
lowed to go unattended, or at most stuffed with oil-meal at night, until 
lameness sets in, when the smith pares the horn around the seat of the 
wound and the patient is returned to work. If the wound has been 
slight there may be no lameness following it whatever, but usually the 
horse is sent to you a week or ten days after the injury with acute lame¬ 
ness from suppuration unrelieved. The wound, which would have re¬ 
covered in a few days’ time from judicious treatment, becomes one of 
importance by reason of the neglect; the inflammation which was at first 
confined to the podophyllous, or to the velvety tissue, extends to the peri¬ 
osteum, and suppuration takes place between the outer and inner layers of 
this membrane, and unless relieved extends over the entire sole. There are 
other cases where no wound can be found, the puncturing instrument being 
so small as to leave no detectable evidence of its passage through the horn, 
and although the animal is lame, you may not be able to make a correct 
diagnosis until suppuration has taken place, and the presence of the pus 
is detected beneath the horn. If the substance of the bone has been 
wounded, you will have the most acute lameness from the moment of 
the injury, superficial ostitis setting in with acute suppurative periostitis. 
