Although dislocations are infrequent, this is the most common form which occurs in the horse.
Cause.—Young loose jointed horses are predisposed to dislocation of the stifle on account of the comparative want of strength of their ligaments. They are much more liable to this accident than older horses, especially if they are in poor health or in rough hilly pastures; the nature of which would naturally make them susceptible to this injury, which, however, may take place as a result of accident at any age. Young horses that suffer, off and on from dislocation, often lose their liability with increasing strength and age. This dislocation may be partial or complete. In the former instance and the most common is where the patella, or the little stifle bone that glides in the groove composed of the lower hip and upper thigh bones, has become partially dislocated or removed from its natural position.
Symptoms.—When the dislocation is complete the affected limb is drawn forward, while the foot from the pastern down is drawn backward, and the animal may throw weight on it when made to move, which is accomplished with great difficulty. When the dislocation is partial, the symptoms are about the same as mentioned, only the limb is less rigid. If the horse is moved, the stifle makes a clicking sound. In this form both limbs may be affected.
Treatment.—In partial dislocation, the stifle bone may be replaced by drawing the leg forward, and with the hand pressing in on the stifle. In complete dislocation, tie a rope around the pastern of the affected leg, then draw the rope through a collar placed around the horse’s neck and draw forward as far as possible and tie. Then press with both hands inward. After the stifle is placed back into position use the following liniment: Aqua Ammonia Fort., four ounces; Oil of Turpentine, four ounces; Raw Linseed Oil, four ounces. Mix and apply well over the stifle joint once or twice a day for two or three days. Feed nourishing food and put the animal to slow, easy work or turn out to good pasture.
In chronic cases of Stifle Joint Lameness, treatment is of no value, therefore, care for the animal as soon as the catch in the walk or lameness appears.
STRING-HALT.
Cause.—Several theories have been put forth as to the cause of String-Halt which is generally supposed to be a nervous disease; a condition opposite to paralysis. The exact cause of this disease is hard to determine, but it is likely to occur in highly nervous horses. It sometimes follows an injury which may have irritated the nerves in some way. I believe that castration causes it in many instances, due to the severe struggle when being thrown, or pulling down severely on the spermatic cord when removing the testicle.
Symptoms.—Spasmodic contraction of one or both limbs. This sign varies, as sometimes it is very violent, while in others it may be so slight that it is hard to detect when stepping the horse forward, but on backing or turning the horse around the signs are easily noticed. All symptoms are better marked in the winter than in the summer, as some show it in the winter that do not show it in the summer at all.
Treatment.—The feeding of laxative foods that are easily digested relieves String-Halt in many instances.