DISSECTION OF THE UPPER EXTREMITY 



79 



(c) Median nerve (N. medianus). How does it arise? Note its 



changing relations as regards the A. brachialis. Does it give off 

 any branches above the elbow? 



(d) Ulnar nerve (N. ulnaris). Study its course in the upper part of 



the arm. Where and how does it leave the anterior compartment 

 of the upper arm? 



FIG. 23. 



Ram. acrom. 



Aa. circ. hum. 



A. prof, hum 



A. thor. sup. 

 ....Ram. pect. 



...A. thor. lat. 



...A. circ. scap. 



A. coll. uln. inf. 



A. rad. recur 



A. recur, uln. ant. 



A. rec. uln. post. 



A. ulnaris 



A. mediana 



Scheme of the branches of the brachial artery. (From Poirier et Charpy, Trait6 d'Anat. hum., Paris, 



1901, t. ii. p. 732, Fig. 416.) 



(e) Musculocutaneous nerve (N. musculocutaneus) . Carefully dissect 

 out this nerve and its branches. How does it arise from 

 the plexus brachialis ? Study its exact course throughout 

 the upper arm. 

 (ea) Muscular rami (rami musculares}. 



(eaa) Nerve to M. coracobrachialis. 



