PARALYSIS OF RADIAL NERVE. 



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be too long. In attempting to move, the upper portions of the limb 

 are carried forward in the ordinary fashion, but cannot support the 

 weight of the body on account of inability to bring the joints into 

 the necessary position. The limb collapses at every attempt to 

 place weight on it. 



The disease is, therefore, characterised by lameness when weight 

 is placed on the limb (supporting leg lameness), flexion of all joints 

 from the elbow downwards, and inability to bring the foot sufficiently 

 forward to enable it to carry weight ; when passively extended, 

 however, the limb is able to sustain the body. On moving the horse 



Fig. 462. — First portion of the stride in a case of paralysis of the radial nerve. 

 The animal was recovering. 



the triceps muscles appear relaxed. They fail to contract, and after 

 some time atrophy. 



In incomplete radial paralysis the weight of the body can be 

 supported provided sufficient muscular power exist to extend the 

 joint. When, therefore, the animal moves slowly, and on a smooth 

 surface, nothing particular is visible, though lameness appears 

 immediately the horse meets with a slight incline or with any obstacle. 

 In such case the foot is not sufficiently extended, it strikes against 

 the obstacle and the leg collapses, so that the horse may fall. 

 Depending on the degree to which nerve or muscle is affected, this 

 stumbling occurs more or less frequently ; sometimes it is only seen 



