104 



ANATOMY IX A NUTSHELL. 



to the fifth, sixth, seventh, and eighth cervica] nerves and the first dorsal nerve. 

 It commences a1 the lower border of the Pectoralis major. It first lies behind 

 the third part of the axillary artery in front of the Subscapulars. Teres major, 

 and Latissimus dorsi. After leaving the axilla it lies on the inner side of the 

 upper one-third of the humerus behind the brachial artery and in front of the 

 long head of the 'Triceps, li passes between the two humeral heads of the 

 Triceps in the musculo-spiraJ groove in company with the superior profunda 

 artery. This nerve and the anterior branch of the superior profunda artery 

 perforate the externa! intermuscular septum and pass in the groove between 

 the Supinator longus and Extensor carpi radialis longior on the outer side, and 



PLATE XXXIX 



8'ceps 



T £ND0N 



,'0BLlQ Ut 



UGAM El u r 



0AB/ CUUfi 

 L 'GAMEH T J" 



The Elbow-Joint — Internal View 



the Brachialis anticus on the inner side. In the lower part of this gr00V< it 

 divides into the posterior interosseous and radial nerves. The musculo-spiral 

 nerve supplies five muscles vi/... Supinator longus, Extensor carpi radialis 

 longior, Triceps, Brachialis anticus and Anconeus. If we substitute Anconeus 

 for heboid we will have the live muscles attached to the external intermus- 

 cular septum. This nerve has muscular branches (just given), an articular 

 branch, cutaneous branches and two terminal branches, viz., posterior interos- 

 seous and radial. 



