NERVES OF THE ARM. 



The ULXAR NERVE ( 4 ), derived from the inner cord of the brachial Uinar nerve 

 plexus, lies close to the inner side at first of the axillary, and then 

 of the brachial artery as far as the insertion of the coraco-brachialis ; 

 then leaving the blood-vessel, it is directed backwards through the 

 inner interrauscular septum to the interval between the olecranon 

 and the internal condyle, being surrounded by the muscular fibres 

 of the triceps. There is not any branch from the nerve till it 

 reaches the elbow-joint. 



The INTERNAL CUTANEOUS (~) is mainly distributed in the fore- 

 arm. Arising from the inner cord of the plexus, it is at first 

 superficial to the brachial artery as far as the middle of the arm, 



is without 

 branch as 

 far as the 

 elbow. 



Internal 

 cutaneous 

 nerve be- 

 neath the 

 fascia. 



FIG. 20. DISSECTION OP THE INNER SIDE OP THE ARM (ILLUSTRATIONS 

 OF DISSECTIONS). 



Muscles : 



A. Pectoralis major. 



B. Biceps. 



c. Coraco-brachialis. 

 D and E, Latissimus and teres. 

 P. Long head of triceps, 

 o. Inner head of triceps. 

 H. Brachialis anticus. 



Vessels: 



a. Brachial artery. 



b. Inferior profunda. 



e. Anastomotic. 



d. Internal vena comes, joining 

 the basilic vein a little above the 

 middle of the arm. 



Nerves : 



1. Median. 



2. Internal cutaneous. 



3. Nerve of Wrisberg. 



4. Ulnar. 



5. Muscular to the triceps. 



6. Internal cutaneous from the 

 musculo -spiral. 



where it divides into two branches that perforate the investing 

 fascia and reach the forearm. Near the axilla it furnishes a small 

 offset to the skin of the front of the arm. 



The NERVE OF WRISBERG (small internal cutaneous 3 ) arises Nerve of 

 with the preceding. Concealed at first by the axillary vein, it is ^ 

 directed inwards beneath (but sometimes through) that vein, and fascia, 

 joins with the intercosto-humeral nerve. Afterwards it lies along 

 the inner part of the arm as far as the middle, where it perforates 

 the fascia to end in the integument. 



D.A. E 



