378 DISEASES OF THE HORSE. 
strong means of support for the stifle joint; that is, of the articulation 
of the thigh and shank bone, in front and outside of which it passes. 
Its situation and its use cause it to be liable to severe stretching 
and straining, and a rupture of some of its fibers is sometimes the 
consequence. 
Cause.—This injury may be the result of a violent effort of the 
animal in leaping over a high obstacle; in missing his foothold and 
suddenly slipping backward while powerfully grasping the ground 
with the feet in striving to start a heavily loaded vehicle; in making 
a violent effort to prevent a probable fall; or in attempting to lift the 
feet from miry ground. 
Symptoms.—The accident is immediately followed by disability 
which will vary according to the true seat of the injury and the 
period of its duration. This rupture will not prevent the horse from 
standing perfectly and firmly on his feet when kept at rest, and 
while no muscular efforts are required from him there is no appear- 
ance of any lesion or unsoundness. An attempt to move him back- 
ward, however, will cause him to throw all his weight upon his hind- 
quarters, and he will refuse to raise his foot from the ground. If 
compelled to do so, or required to move forward, the hock being no 
longer capable of flexion, the muscle which effects that movement 
being the injured one, the opposite muscles, the extensors, acting 
freely, the entire lower part of the leg, from the hock down, will 
be suddenly, with a jerk, extended on the tibia or shank bone, and 
simultaneously with this the tendo Achillis, the cord of the hock, the 
tendons of the extensors of the hock will be put in a wrinkled and 
relaxed condition. The leg is behind the animal and the toe rests 
on the ground. Examination of the fore part of the shank from the 
stifle down to the hock may reveal soreness, and possibly some 
swelling and heat at the seat of the lesion. 
Treatment.—Our experience with injuries of this form convinces 
us that, generally speaking, they are amenable to treatment. . Pro- 
vided a sufficient time has been allowed for union to take place, very 
few instances in which radical recovery has not been effected have 
come to our knowledge. The more flexed the leg can be kept, the 
quicker will it heal. 
In these cases, as in those of simple laceration of tendons, already 
considered, the indications resemble those which apply in the treat- 
ment of fractures, as near as coaptation of the lacerated ends is pos- 
sible, with immobility, being the necessary conditions to secure. The 
first is a matter of very difficult accomplishment, by bandaging alone, 
and some have recommended instead the application of charges or 
blisters in order to compel the animal to keep more quiet. 
To secure the necessary immobility the animal should be placed in 
slings snugly applied, and kept in a narrow stall. He should also be 
