384 DISLOCATION OF THE PATELLA. — THOROUGII-riN. 



length of the muscle is the degree of contraction of which it is capable ; 

 and also in proportion to the contraction of the muscle is the extent of 

 motion in the limb : but it is still more necessary that this part of the 

 thigh should have considerable muscle, in order that sti'eng-th may be 

 added to such extent or compass of motion. Much endurance would not 

 be expected from a horse with a thin arm. A horse with thin and lanky 

 thighs will not possess the strength which considerable exertion would 

 sometimes require. The principal muscles of this part of the thigh are 

 usually somewhat prominent, and may readily be traced in the living 

 animal. 



SPRAIN OF THE STIFLE. 



The stifle-joint is occasionally subject to sprain from some violent exertion 

 or sudden slip of the animal. From its somewhat exposed position, it is 

 also liable to injury, either from the kick of another horse, or from coming 

 in contact with some hard substance. In these cases there will generally 

 be sufficient heat, tenderness, and swelling in the part to point out the 

 seat of injury. The animal will also step short on the affected limb, being 

 unable to extend it. The treatment should consist in resting the animal, 

 apjjlying warm fomentations to the part, and administering a dose of 

 physic. If the inflammation runs very high it may be further reheved by 

 bleeding from the femoral vein. When the acute sjrmptoms have sub- 

 sided, a blister may be apphed to the part. 



DISLOCATION OF THE PATELLA. 



This is not a very uncommon disease, and may arise from several causes, 

 such as a congenitally relaxed condition of the hgaments of the joints, and 

 weak state of the muscles. It is sometimes caused by some inordinate 

 force, siich as muscular contraction, especially when the condyles over 

 which the patella plays are not sufficiently developed. Cramp and sudden 

 unconscious movements will also produce it, and it frequently follows de- 

 bilitating diseases such as influenza, fever, &c. Young well-bred animals 

 are particularly subject to this affection. The symptoms are weU marked 

 and Avill not easily be mistaken. The animal is quite unable to move or 

 extend the injured limb, and a careful examination -will generally detect 

 an unnatural enlargement on the outside of the stifle-joint. The aid of 

 the veterinary surgeon is here requisite ; still, however, an attempt 

 should be made to reduce the dislocation as soon as it is discovered. A 

 strap should be placed below the fetlock -joint, and the limb di-awn forward 

 by an assistant as far under the abdomen as possible ; the operator should 

 then steadily press the patella in an inward, downward, and forward 

 direction, when a moderate degree of force will generally replace it. The 

 animal should then be tied up and not allowed to he do^^Ti for some time, 

 and a blister apphed over the whole surface of the joint, or in bad cases, 

 the actual cautery may be used. In young animals we sometimes get a 

 kind of partial dislocation of the pateUa ; it sHps partly ofi" the condyle, 

 and when the animal moves a peculiar snapping sound is heard. This 

 is a result of a relaxed condition of the ligaments of the joint and gen- 

 erally disappears as the animal gets older, especially if the joint has been 

 repeatedly bhstered. 



THOROUGH-PIN. 



Mention has been made of wind-galls and their treatment. A similar 

 enlargement is found above the hock, between the tendons of the flexor of 

 the foot and the extensor of the hock. As from its situation it generally 

 projects on both sides of the hock, in the form of a round swellijig, it 



