DISEASES OF THE FETLOCK, ANKLE, AND FOOT. 427 
their depth, involve the plantar cushion, the plantar aponeurosis, 
the sesamoid sheath, the navicular bone, or the coffin joint. 
Punctured wounds are more liable to be deep in flat or convex feet 
than in well-made feet, and as a rule, recovery is neither so rapid nor 
so certain. These wounds are less serious in animals used for heavy 
draft than in those required to do faster work; for the former may be 
useful, even if complete recovery is not effected. Lastly, punctured 
wounds of the fore feet are more serious than of the hind feet, for the 
reason that in the former the instrument is liable to enter the foot in 
a nearly perpendicular line, and, consequently, is more liable to 
injure the deeper structures of the foot; in the hind foot, the injury 
is generally near the heels and the wound oblique and less deep. 
Symptoms.—A. nail or other sharp instrument may penetrate the 
frog and remain for several days without causing lameness; in fact, 
in many cases of punctured wound of the frog. the first evidence of 
the injury 1s the finding of the nail or the appearance of an opening 
where the skin and frog unite, from which more or less pus escapes. 
Eyen when the sole is perforated, if the injury is not too deep, no 
lameness develops until suppuration is established. In all cases of 
foot lameness, especially if the cause is obscure, the foot should be 
examined for evidence of injury. 
The lameness from punctured wounds, accompanied with suppu- 
ration, is generally severe, the patient often refusing to use the 
affected member at all. The pain being lancinating in character, 
he stands with the injured foot at rest or constantly moves it back 
and forth. In other cases the patient lies down most of the time 
with the feet outstretched ; the breathing is rapid, the pulse fast, the 
temperature elevated, and the body covered with patches of sweat. 
When the plantar aponeurosis is injured, the pus escapes with diffi- 
culty and the wound shows no signs of healing; the whole foot is 
hot and very painful. If the puncture involves the sesamoid sheath, 
the synovial fluid escapes. At first this fluid is pure, like joint water, 
but later becomes mixed with the products of suppuration and 
loses its clear, amber color. Suppuration generally extends up the 
course of the flexor tendon, an abscess forms in the hollow of the 
heel, and finally opens somewhere below the fetlock joint. The 
whole coronet is more or less swollen, the discharge is profuse and 
often mixed with blood, yet the suffering is greatly relieved from 
the moment the abscess opens. 
If the puncture reaches the navicular bone the lameness is intense 
from the beginning; but the only certain way to determine the 
existence of this complication is by the use of the probe; and unless 
there is a free escape of synovia it. must be used with the greatest 
of care, else the coffin joint may be opened. 
