350 ■ ABRAM T. KERR 



In Wichmann's tabulation, the eighth cervical and first thoracic 

 are credited with sending fibers to the nerve in 9 cases, the first 

 thoracic in 84 and the seventh cervical in 1. 



THE MEDIAL ANTIBRACHIAL CUTANEOUS NERVE 



The medial antibrachial cutaneous (internal cutaneous, ulnar 

 antibrachial cutaneous) nerve is usually described as arising from 

 the caudal trunk of the brachial plexus. 



There are 174 satisfactory records in my series. There are 

 95 of these in which the nerve arises from the medial fasciculus 

 of the plexus singly and with no anastomosis with the intercosto- 

 brachial. In 86 of these there are no anastomoses with any 

 nerve (fig. 4) ; in 3 the nerve receives a branch from the medial 

 anterior thoracic nerve; in one it receives a branch from the 

 caudal trunk, a sort of second head; in 2 a branch from the 

 medial brachial cutaneous joins it and in 4 it sends a branch to 

 this nerve. There are 10 other plexuses in which the medial 

 antibrachial cutaneous nerve arises from the medial fasciculus 

 of the plexus but it anastomoses wdth the intercostobrachial in 

 these, and in one of them it receives a branch from the medial 

 brachial cutaneous nerve. 



There are 36 cases in which the medial antibrachial cutaneous 

 nerve arises from the medial fasciculus of the plexus from a stem 

 common to it and some other nerve. In 19 cases it arises with 

 the medial brachial cutaneous (fig. 6); in 8 with the medial 

 anterior thoracic; and in 7 with both of these nerves (fig. 1). 

 In 17 of these cases there is no anastomosis with the intercos- 

 tobrachial but in the 2 other cases there is. In one of these it 

 arises with the medial brachial cutaneous and sends a branch 

 to the radial ; in the other, with the medial anterior thoracic and 

 receives a branch from the medial brachial cutaneous. 



The medial antibrachial cutaneous nerve arises from the cau- 

 dal trunk of the plexus singly and without anastomosing with 

 the intercostobrachial in 12 instances (fig. 2). In one of these 

 there are 2 roots ; in one it received a branch from the medial 

 brachial cutaneous; and in one it gives a branch to the radial 

 nerve. There are 4 other cases in which the nerve arises from 



