134 SURGICAL ANATOMY OF THE AXILLA. 



and minor and their aponeuroses, and the lower border 

 of the former covered by the integuments constitutes its 

 anterior inferior margin. In the female this margin is 

 hidden by the mammary gland, which overhangs it. 

 The position of this gland is not influenced by the move- 

 ments of the shoulder upon the trunk, as the cellular 

 membrane between it and the anterior layer of the sheath 

 of the pectoralis major permits of the free motion of the 

 muscle beneath it; but in the case of scirrhus, owing to 

 infiltration of the tissues, the movements of the pectoral 

 are made with great pain and difficulty. On the pos- 

 terior surface of these muscles are seen the acromio- 

 thoracic vessels and external and internal anterior tho- 

 racic nerves. 



The posterior wall is formed by the teres major and 

 latissimus dorsi muscles below, and by the subscapularis 

 above with their vascular and nervous supply. 



The apex of the axilla may be referred to the coracoid 

 process, though more correctly to the aperture between 

 the clavicle, upper border of scapula, and first rib, with 

 their muscular coverings. The cellular tissue of the 

 cavity of the axilla, becomes continuous with that of the 

 subclavian region at the apex by enveloping the vessels 

 that pass through this interspace. 



The axillary artery, axillary vein, and brachial plexus 

 form a vasculo-nervous cord, bound together by a dense 

 cellular sheath which is placed on the outer wall of the 

 space, and lying along the inner border of the coraco- 

 brachialis muscle ; the pulsations of the artery are felt at 

 the apex (if the pectoralis major is relaxed), and at its 

 lower portion, and in thin persons, the cord of the median 

 nerve is usually seen stretched over it when the arm is 

 raised from the side. The course of this vessel is indi- 



