144 PARTICULAR FRACTURES. 



Partial disolocation of the Fetlock Joints, arising from 

 of the feet, over- work, or a natural tendency to " knuckle over," 

 is an occurrence of which little need be said, and with the 

 exception of rest and perhaps a hUster, no treatment can be 

 recommended.^ 



This form of unsoundness may also arise from relaxation of 

 the binding ligaments, and this may be the result of chronic 

 inflammation of them, leading to a degeneration of their proper 

 structure, when they will be found pulpy, more or less thick- 

 ened, and the areolar tissue which is amongst their fibres highly 

 vascular. 



The hcai of the Femur may be dislocated in the ox, dog, and 

 cat ; but in the horse tliis is an impossibility without fracture, 

 owing to the fact that in the horse the " j^uhio femoral ligament" 

 is found. This ligament arises from the head of the femur, passes 

 from the acetabulum through the cotyloid notch, then runs along 

 a grove on the under side of the pubis to the median line, where 

 it crosses its fellow from the opposite side, forming a cross, X. 

 and becomes finally lost in the faschia of the abdominal muscles. 

 In this manner the head of each femoral bone is kept in position 

 by the muscles of the opposite side of the abdomen. Eeduc- 

 tion may be easily effected in the dog and cat by extension and 

 manipulation, and the parts maintained in position by a stifl 

 Burgundy pitch plaster ; but in the cow any treatment may be 

 considered questionable, and if the animal is at all fat, she should 

 be made into beef. 



The symptoms of this dislocation are similar to those of 

 fracture, but there will be no crepitation. As a rule, in the 

 dog and cat the dislocated bone will be found on the dorsum 

 of the ilium. There will be shortening of the limb, and total 

 inability on the part of the patient to perform the ordinary 

 movements ; but should the dislocation be into the foramen 

 ovale, the limb will appear longer than its fellow, and the foot 

 turned outwards. 



Dislocation of the Carpus, or of one of the phalanges, is of com- 



* Note. — Since the above has been in type, I have had the opportunity of dis- 

 secting a limb, where habitual "knuckling over" at the fetlock was found to be 

 due to an arrested development of the extensor suffrayinis. The tendon of this 

 muscle terminated at the upper head of the metacarpus parvus externus, the action 

 of the extensor muscle thus terminating at the knee, and the fetlock knuckled over 

 from the want of the support of its tendon. 



