DISEASES OF THE FETLOCK, ANKLE, AND FOOT. 
By A, A. Hotcomser, D. Y. &., 
Veterinary Inspector, Bureau of Animal Industry. 
ANATOMICAL REVIEW OF THE FOOT. 
In a description of the foot of the horse it is customary to include 
only the hoof and its contents, yet, from a zoological standpoint, the 
foot includes all thé leg from the knee and the hock down. 
The foot of the horse is undoubtedly the most important part of 
the animal, so far as veterinary surgery is concerned, for the reason 
that it is subject to so many injuries and diseases which in part or 
in whole render the. patient unfit for the labor demanded of him. 
The old aphorism “no foot no horse” is as true to-day as when first 
expressed; in fact, domestication, coupled with the multiplied uses 
to which the animal is put, and the constant reproduction of heredi- 
tary defects and tendencies, has largely transformed the ancient 
“companion of the wind” into a very common piece of machinery 
which is often out of repair, and at best is but shortlived in its use- 
fulness. 
Since the value of the horse depends largely or even entirely upon 
his ability to labor, it is essential that his organs of locomotion be 
kept sound. To accomplish this end it is necessary not only to know 
how to cure all diseases to which these organs are liable but, better 
still, how to prevent them. 
An important prerequisite to the detection and cure of disease is a 
knowledge of the construction and function of the parts which may 
be involved in the diseased process. Hence, first of all, the anatomical 
structures must be understood. (See also p. 583.) 
The bones of the fetlock and foot constitute the skeleton on which 
the other structures are built and comprise the lower end of the can- 
non bone (the metacarpus in the fore leg, the metatarsus in the hind 
leg), the two sesamoids, the large pastern or os suffraginis, the small 
pastern or coronet, the small sesamoid or navicular bone, and the 
coffin bone or os pedis. (Plate XX XTV, fig. 3.) 
The cannon bone extends from the knee or hock to the fetlock, is 
cylindrical in shape, and stands nearly or quite perpendicular. 
The sesamoids occur in pairs, are small, shaped like a three-faced 
pyramid, and are set behind the fetlock joint, at the upper end of the 
large pastern, with the base of the pyramid down. 
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