THE SHOULDER. SPRAIN JF THE SHOULDER. 255 



CHAPTER XII. 

 THE FORE LEGS. 



WE am>e now a, those parts of the frame which are most essentially cumaicted 

 writh the astion and \ralue of the horse, and oftenest, and most annoyingly, the subjects 

 of disease. The extremities contain the whole apparatus of voluntary motion, with 

 which the action, and speed, and strength of the horse are most concerned. 



We commence with the upper portion, of which the fore extremity, the shoulder 

 is seen at G, p. 68. 



THE SHOULDER. 



The scapula or shoulder-blade, situated forward on the side of the chest, is a bone 

 of a somewhat triangular shape, with its apex or narrowest point downward, and its 

 broad and thin expansion upward. The point of the shoulder lies opposite to the first 

 and second ribs ; the hinder expansion of the base reaches as far back as the seventh 

 rib ; it therefore extends obliquely along the chest. It is divided, externally, into twc 

 unequal portions by a ridge or spine running through almost the whole of its extent, 

 and designed, as will be presently seen, for the attachment of important muscles. 

 The broad or upper part having no muscles of any consequence attached to it, is 

 terminated by cartilage. 



The shoulder-blade is united to the chest by muscle alone. There is one large 

 muscle, with very remarkable tendinous fibres and of immense strength (the serratus 

 major, greater saw-shaped muscle), attached to the chest, and to the extensive smooth 

 internal surface of the shoulder-blade, and by which, assisted, or rather strengthened, 

 by the muscles of the breast, the weight of the body is supported, and the shock of 

 the widest leap, or the most rapid motion, sustained. Had there been a bony union 

 between the shoulder and the body, the vital parts contained in the chest could not 

 have endured the dreadful, shock which they would occasionally have experienced ; 

 nor could any bone have long remained whole if exposed to such violence. The 

 muscles within the shoulder-blade act as powerful and safe springs. They yield, as 

 far as necessary, to the force impressed upon them. By their gradual yielding they 

 destroy the violence of the shock, and then by their elastic power, immediately regain 

 their former situation. 



SPRAIN OF THE SHOULDER. 



These muscles are occasionally injured by some unexpected shock. Although in 

 not more than one case in twenty is the farrier right when he talks of his shoulder- 

 lameness, yet it cannot be denied, that the muscles of the shoulder are occasionally 

 sprained. This is effected oftener by a slip or side-fall, than by fair, although violent 

 exertion. It is of considerable importance to be able to distinguish this shoulder- 

 lameness from injuries of other parts of the fore extremity. There is not much 

 tenderness, or heat, or swelling. It is a sprain of muscles deeply seated, and where 

 these symptoms of injury are not immediately evident. If, on standing before the 

 horse, and looking at the size of the two shoulders, or rather their points, one should 

 appear evidently larger than the other, this must not be considered as indicative of 

 sprain of the muscles of the shoulder. It probably arises from bruise of the point of 

 the shoulder, which a slight examination will determine. 



The symptoms, however, of shoulder-lameness can scarcely be mistaken ; and, 

 whf n we relate them, the farmer will recollect that they very seldom occurred when 

 the village smith pointed to the shoulder as the seat of disease, and punished the 

 anim il to no purpose. In sprain of the shoulder the horse evidently suffers extreme 

 pain virile moving, and, the muscle underneath being inflamed and tender, he will 

 extend it as little as possible. He will drag his toe along the ground. It is in the 

 lifting of the foot that the shoulder is principally moved. If the foot is lifted high, 

 let the horse be ever so lame, the shoulder is little, if at all affected. In sprain of the 

 iwck sinews, it is only when the horse is in motion that the injured parts are put it) 

 most pain ; the pain is greatest here when the weight rests on the limb in shoulder- 

 .ameness, and there is a peculiar quickness in catching up the limb the moment th* 



