THE AXILLA. 



259 



Internally. To the inner side of the artery and somewhat anteriorly is the 

 axillary vein; between the two runs the internal anterior thoracic nerve. As the 

 artery and vein ascend they become separated, the artery to pass behind and the 

 vein in front of the scalenus anterior muscle. 



Externally. To the outer side and above the artery lie the cords of the 

 brachial plexus. 



Anteriorly. In front of the artery are the skin and superficial fascia, the edge 

 of the pectoralis major muscle and fascia covering it, the costocoracoid membrane 

 pierced by the acromiothoracic artery, cephalic vein, and external anterior thoracic 

 nerve, which goes to supply the pectoralis major muscle. 



Ligation of the First Portion of the Axillary Artery. The artery lies 

 deep in the infraclavicular triangle, between the pectoralis major and deltoid muscles. 

 It can be approached by either a transverse or a longitudinal incision. If the former 

 is used it should be made through the skin only, immediately below the clavicle, 

 reaching from just outside the sternoclavicular joint to the coracoid process. 



The pectoralis major is detached from the clavicle and pushed downward, it 

 arises from its inner half. This exposes the costocoracoid membrane. At the outer 



Pectoralis minor 



Acromiothoracic 



Long thoracic 



Pectoralis major 



Biceps 



Alar thoracic 



Subscapular 

 Posterior circumflex 



issimus dorsi 



v 



Triceps 

 FIG. 271. Diagrammatic view of axillary artery and its branches. 



angle of the wound the cephalic vein and acromiothoracic artery are to be found. 



The deltoid muscle is to be detached or pushed outward to expose the coracoid 

 process, this being recognized, the costocoracoid membrane is to be opened to its 

 inner side, between it and the cephalic vein. The acromiothoracic artery if isolated 

 will lead to the artery, while the cephalic vein goes direct to the subclavian vein. 

 The vein and costocoracoid membrane are closely united and great care is necessary 

 to avoid wounding the former in opening the latter. The cords of the brachial 

 plexus are to the outer side of the artery and care is to be exercised not to mistake 

 one of them for the artery. As the vein is the most dangerous structure, it is to be 

 displaced inward and the aneurism needle passed between it and the artery from 

 within outward. 



As the external anterior thoracic nerve is a nerve of motion supplying the 

 pectoralis major muscle, if it is seen it should be avoided and not injured. 



If it is desired to use a longitudinal instead of transverse incision, it should com- 

 mence just outside the middle of the clavicle and follow the groove between the deltoid 

 and pectoralis major muscles downward for 10 cm. (6 in. ). Great care is then neces- 

 sary to avoid wounding the cephalic vein and acromiothoracic artery, which lie in this 

 groove. 



If sufficient exposure is not given by a single straight incision it can be supple- 

 mented by one detaching the pectoralis major from the clavicle. 



