AXILLARY SPACE 19 



the axilla. After the nerve has been secured the serratus anterior must be 

 cleaned. When this has been done the dissector should clean the lower 

 parts of the axillary vessels and nerves and their branches and tributaries. 

 Commence at the lower border of the pectoralis minor and find the 

 subscapular artery. It springs from the medial and posterior part of the 

 axillary trunk and runs distally and medially along the lower border of 

 the subscapularis muscle. Follow the artery and, whilst doing so, clean the 

 posterior group of the axillary lymph glands which lie along its course and 

 secure the thoracodorsal nerve (long subscapular), which joins the artery 

 near the junction of the lateral and posterior walls of the axilla and ter- 

 minates in the latissimus dorsi, which it supplies. Rising from the upper 

 part of the subscapular artery is its large circumflex scapular branch which 

 passes backwards through the posterior wall of the axilla. In the angle be- 

 tween this branch and the main trunk will be found the lower subscapular 

 nerve which supplies the teres major and the lower fibres of the subscapularis. 

 The dissector should now thoroughly clean the lower part of the axillary 

 artery and vein, the medial cutaneous nerve of the forearm which lies in 

 the angle between them anteriorly, and the median cutaneous nerve of the 

 arm which lies along the medial side of the vein ; then he should pull the 

 vein forwards and laterally, and in the angle between it and the artery, 

 posteriorly, he will find the ulnar nerve ; this also should be pulled forwards 

 and laterally to display the axillary (circumflex) nerve, which turns back- 

 wards at the lower border of the subscapularis above the level of the 

 circumflex scapular artery, and the radial (musculo-spiral) nerve, which 

 descends behind the axillary artery to the lower border of the axilla. Spring- 

 ing from the upper part of the radial (musculo-spiral) nerve are '^posterior 

 brachial cntaneotts branch and muscular branches to the long and medial 

 heads of the triceps muscle ; these branches may rise separately from the 

 radial nerve or they spring from it by a common trunk which afterwards 

 divides into the individual branches. Trace 'the posterior brachial 

 cutaneous nerve to the back of the arm behind the intercosto-brachial 

 nerve ; follow the nerve to the long head of the triceps till it enters the 

 muscle. The nerve to the medial head of the triceps is usually a long 

 slender branch which is known as the ulnar collateral nerve because it 

 accompanies the ulnar nerve to the lower part of the arm. It will be 

 traced to its termination at a later period. The anterior and posterior 

 humeral circumflex branches of the axillary artery .will be found springing 

 from the artery a short distance below the subscapular branch, the 

 former rising from the anterior and the latter from the posterior aspect of 

 the axillary trunk. 



When the lower part of the axilla has been thoroughly cleaned, the 

 pectoralis minor must be divided, about midway between its origin and 

 insertion, and the two parts must be turned aside. When this has been 

 done the upper subscapular nerve must be found entering the upper part 

 of the subscapularis, and then the remaining areolar tissue must be removed 

 from the axillary space, the trunks and branches of the axillary vessels and 

 nerves must be thoroughly cleaned, and the contents of the space must be 

 studied in detail. 



Lymphoglandulse Axillares (Axillary Lymph Glands). 



The lymph glands in the axillary region are spoken of, 

 collectively, as the axillary glands, but for convenience of 

 description, and to facilitate a more precise knowledge of 

 their connections and associations, they are subdivided into 



