338 DISEASES OF THE HOKSB. 



it — outward, inward, backward, or forward — and the deformity 

 which results and the effects which follow will correspondingly differ. 

 We have said that treatment is generally unsuccessful. It may be 

 added that the difficulties which interpose in the way of reduction are 

 nearly insurmountable, and that the application of means for the 

 retention of the parts after reduction would be next to impossible. 

 The prognosis is sufficiently grave from any point of view for the 

 luckless animal with a dislocated shoulder. 



THE HIP JOINT. 



This joint partakes very much of the characteristics of the humero- 

 scapular articulation, but is more strongly built. The head of the 

 thigh bone is more separated, or prominent and rounder in form, and 

 the cuplike cavity, or socket, into which it fits is much deeper, form- 

 ing together a deep, true ball-and'-socket joint, which is, moreover, 

 reenforced by two strong cords of funicular ligaments, which unite 

 them together. It will be easily comprehended, from this hint of the 

 anatomy of the region, that a luxation of the hip joint must be an 

 accident of comparatively rare occurrence. And yet cases are recorded 

 in which the head of the bone has been affirmed to slip out of its 

 cavity and assume various positions — inward, outward, forward, or 

 backward. 



The indications of treatment are those of all cases of dislocation. 

 When the reduction is accomplished the surgeon will be apprised 

 of the fact by the peculiar snapping sound usually heard on such 

 occasions. 



PSEtTDO-LtrXATIONS OF THE PATELLA. 



This is not a true dislocation. The stifle bone is so peculiarly 

 articulated with the thigh bone that the means of unioh are of suffi- 

 cient strength to resist the causes which usually give rise to luxations. 

 Yet there is sometimes discovered a peculiar pathological state in the 

 hind legs of animals, the effect of which is closely to simulate the 

 manifestation of many of the general symptoms of dislocations. This 

 peculiar pathological condition originates in muscular cramps, the 

 action of which is seen in a certain change in the coaptation of the 

 articular surfaces of the stifle and thigh bone, resulting in the exhibi- 

 tion of a sudden and alarming series of symptoms which have sug- 

 gested the phrase of " stifle out " as a descriptive term. 



SymptoTTis. — ^The animal so affected stands quietly and firmly in his 

 stall, or perhaps with one of his hind legs extended backward, and 

 resists every attempt to move him backward. If urged to move for- 

 ward he will either refuse or comply with a jump, with the toe of 

 the disabled leg dragging on the ground and brought forward by a 

 second effort. There is no flexion at the hock and no motion at the 

 stifle, while the circular motion of the hip is quite free. The leg 

 appears to be much longer than the other, owing to the straightened 



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