THE BRACHIAL PLEXIX 



i wiiJ'Ue trunk ; and the eighth cervical and first dorsal join beneath 



the anterior scalenus in a //'</ trunk. Xeur the outer border of 



av 



- 



FIG. 216. DIAGRAM OF THE BRACHIAL PLEXUS. THE DOTTED LINE IXM- 

 CATKS THE LEVEL AT WHICH THE CORDS ARK CROSSED BY THE CLAVICLE. 



civ. to cvin. Fourth to eighth 

 cervical nerves. 



DI, and DII. First and second 

 dorsal nerves. 



li, and 2i. First and second inter- 

 costal nerves. 



phr. Phrenic nerve, 

 rh." Xerve to rhomboids, 

 pt. Posterior thoracic nerve, 

 sc. Branch to subclavius. 

 sps. Suprascapular nerve. 



the middle scalenus these three trunks bifurcate, each giving off an 



,. . . divides 



anterior and a posterior dinsio//.. As they pass beneath the into 



clavicle the anterior divisions of the upper and middle trunks join 



posterior 

 branches. 



