SECTION X 

 THE BLOODVESSELS OF THE UPPER LIMB 



Arteries of the Upper Limb. 



THE blood-supply of the upper limb is derived from the con- 

 tinuation of the subclavian artery, which at the lower border 

 of the first rib changes its name and becomes the axillary 

 artery. 



Axillary Artery. From the lower border of the first rib to 

 the lower border of the teres major. 



The axillary artery passes through the axillary space, and lies 

 on, successively, upper digitation of serratus magnus, sub- 

 scapularis, latissimus dorsi, teres major, and is covered by pec- 

 tor alis major and minor. 



The pectoralis minor muscle crosses the middle third of the 

 artery and divides it into three parts. 



The three cords of the brachial plexus lie respectively to the 

 inner, outer, and posterior sides of the artery. 



The axillary vein lies along the inner side of the artery. 



Branches. From first and second parts : 



Several thoracic branches to supply the neighbouring parts. 

 From third part : 



1. Subscapular, which arises opposite the lower border of the 

 scapularis and supplies the adjacent muscles and inner wall of 

 axillary space. 



2. Anterior and Posterior Circumflex, which enclose the sur- 

 gical neck of the humerus and supply the shoulder-joint and 

 adjacent muscles (see Fig. 6). 



The axillary artery is continued as the brachial artery, which 

 passes down to supply the upper arm. 



Brachial Artery. From the lower border 'of teres major to 

 the antecubital fossa, where, at the level of the neck of the 



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