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CHAPTER IX. 

 NERVE INJURIES. 



The effects of nerve section. Epicritic, protopathic, and deep 

 sensibility. Causation of trophic lesions. Diagnosis of partial 

 nerve section. How degenerated nerve is regenerated. The 

 results of primary and secondary nerve suture. Methods of dealing 

 with wide gaps. 



IT will be necessary in compressing this immense 

 subject into the limits of a single chapter simply 

 to mention the better-known phenomena, and refer 

 to the original monographs those who wish to become 

 .more fully acquainted with the interesting results 

 here alluded to. 



THE EFFECTS OF DIVISION OF A NERVE. 



The effects of division of a nerve are as follows : 



(a). Flaccid paralysis of the muscles supplied, with 

 loss of reflexes. 



(b). Loss of epicritic sense over the anatomical 

 area supplied by the nerve. Loss of protopathic 

 sense over an area, usually smaller and encircled by 

 the former. Sometimes loss of deep sensibility over 

 an area smaller still. (These terms are explained 

 subsequently.) 



(c). Reaction of degeneration. 



(d). Wasting of muscles. 



(e). Paralysis of the pilomotor nerves, so that the 

 hairs lie irregularly, and " goose skin " does not so 

 readily occur. 



