Lesions of Nerves of Uppet Limb. 1 1 1 



carried this far by the supinator, the weight of the hand 

 will cause it to fall inwards, i.e., to pronate it. Flexion of 

 the fingers is interfered with, from paralysis of the super- 

 ficial and some of the deep flexors. The inner half of the 

 flexor profundus can still flex the last phalanges of the 

 little and ring fingers, while the interossei, along with the 

 two inner lumbricales, can flex the first phalanges of all 

 the fingers since these muscles are supplied by the intact 

 ulnar nerve. Abduction and flexion of the thumb is in- 

 terfered with, while median and radial flexion of the wrist 

 is lost, although ulnar flexion is not, since the unaffected 

 flexor carpi ulnaris can still act. Anaesthesia is present 

 over the middle and outer side of the palm of the hand, 

 and over most of the thumb, index, middle and the outer 

 half of the ring fingers. The unopposed action of the in- 

 tact muscles will cause the forearm to be partially supi- 

 nated and the fingers and thumb extended. 



Ulnar Nerve. This nerve supplies the inner 

 half of the flexor profundus, and hence flexion of 

 the third phalanges of the little and ring fingers will be 

 lost. Ulnar flexion of the wrist is lost, and the interossei 

 and the two inner lumbricales being paralyzed, it is im- 

 possible to flex the first, or to extend the second and third 

 phalanges of the fingers, and, therefore, the first phalanx 

 is extended by the common extensor, and the second and 

 third phalanges are flexed by the unopposed long flexor 

 tendons, giving a "claw-like" appearance to the the hand, 

 while the thumb is abducted and slightly extended. 



