350 CHAPTER 45. 



If pushed back, the patella will often slip again into its place. If it 

 does not do so, a rope must be secured round the pastern, and the leg 

 must then be drawn forward by one assistant, whilst another presses on 

 the outer and upper part of the patella, and pushes it in an inward and 

 forward direction. 



Its replacement will be indicated by a sudden snap. It will sometimes 

 be found that, as soon as the hand is removed after replacing the bone, 

 it slips out again. When such is the case, the operator should continue 

 his pressure on the part for an hour or longer. The horse must be re- 

 strained from lying down for two or three days, and a mild vesicant may 

 be applied to produce soreness of the skin, and thus prevent the animal 

 from moving the leg. 



When the patella has once been displaced, there is a tendency for the 

 accident to recur, again and again. In such cases it will be necessary to 

 blister over the part. The effusion and thickening thus produced may 

 exercise, as it were, persistent pressure on the part. 



The stifle joint is also subject to general inflammation of its synovial 

 membrane from the effect of injuries. 



708. Sprains of the Fetlock joint. 



The injury is much the same as that which occurs in the similar joint 

 in the fore-leg, mentioned in paragraph 691 in the preceding chapter, and 

 the causes are usually the same. It may, however, arise from repeated 

 sprains of the flexor tendons which pass over the joint. 



Knuckling over behind, as distinguished from sprain of the joint, is 

 most frequently caused by spavin, or some other such cause which inter- 

 feres with the due flexion of the hock ; or excessive work while the tissues 

 are immature. 



709. Sprains of the Loins. 



This injury consists of sprains of the ligaments connecting the dorsal 

 and lumbar vertebrae, or it may be sprain of the psoae muscles. 



Horses so affected roll in their hind quarters and have not proper 

 control over the muscles. The injury generally occurs very suddenly, 

 and is the result of some violent over-exertion. The treatment is long 

 rest and repeated blisters. Adhesive plasters, commonly called charges, 

 have been found beneficial, especially when recovering. 



The chance of recovery is very uncertain. If the injury is at all severe, 

 the better plan is to destroy the animal. If the injury is very slight, the 

 animal may move pretty well in a straight direction ; but the injury will 

 be detected when the horse is backed or turned round. This trial should 

 never be omitted in the examination of a horse as to soundness. 



