BRACHIAL PLEXUS OF NERVES IN MAN 365 



From those cases in which my records show the branches of the 

 axillary subscapular nerve to the subscapularis muscle, it will 

 be seen that in 21 instances there is a single branch; in 15 there 

 are 2 branches, besides 3 cases in which there is one branch from 

 the axillary subscapular nerve and a second branch from the 

 axillary nerve close to it, and one case in which there are two 

 branches from the axillary nerve to the subscapularis muscle, 

 and none from the axillary subscapular nerve. 



There are 5 cases in which there are three nerves to the axillary 

 part of the subscapularis muscle. In 2 of these all three came 

 from the axillary subscapular, in 2 cases two come from the 

 axillary subscapular, and the third from the posterior fasciculus, 

 and in the fifth case two branches come from the axillary sub- 

 scapular and the third from the axillary nerve close to it. 



In one plexus there are four branches from the axillary sub- 

 scapular nerve to the axillary part of the subscapularis muscle. 



There are 115 plexuses in which I cannot be sure that fibers 

 from all the nerves of the plexus may not enter the axillary sub- 

 scapular nerve. In 79 of these the nerves from the fourth cervi- 

 cal to the first thoracic may send fibers and in 36 from the fifth 

 cervical to the first thoracic. In one case fibers may come from 

 the fourth to the eighth cervical and in two from the fifth to the 

 eighth; in 14 from the fourth to the seventh cervical and in 12 

 from the fifth to the seventh. In 6 cases the fourth, fifth and 

 sixth cervical are the only nerves and in 4 the fifth and sixth. 

 In one the seventh cervical and in 2 the seventh and eighth cervi- 

 cal and first thoracic may contribute. 



Herringham was able to exclude the eighth cervical and first 

 thoracic nerves from the axillary subscapular in all of his 41 cases. 

 He found it arising from the fifth, sixth and seventh cervical 

 nerves in 3 cases; the sixth and seventh in 9. The seventh nerve 

 contributing to the plexus only in these 12 cases. The nerve 

 arises from the fifth and sixth cervical nerves in 9 cases and from 

 a trunk formed by branches of these nerves in 13 cases or 22 in 

 all where the fifth and sixth may have formed the nerve. The 

 sixth alone in 4 and the fifth alone in 3 cases formed this nerve. 



THE AMERICAN JOURNAL OF ANATOMY, VOL. 23, NO. 2 



