THE UPPER LIMB 



309 



origin of the platysma myoides, deep fascia, clavicular part of the 

 pectoralis major, costo-coracoid membrane, axillary sheath, and 

 the lower border of the subclavins when the shoulder is de- 

 pressed. It is also crossed by the cephalic and acromio- thoracic 

 veins, and the commimicating loop between the external and 

 internal anterior thoracic nerv^es. Posteriorly it rests upon the 

 first intercostal space, the first serration of the serratus magnus, 

 and the upper portion of the second rib, with the intervention of 



g 10 ti 12 13 



Long Head of Biceps 

 Tendon of Pectoralis Major 

 Short Head of Biceps 

 Coraco-brachialis 

 Posterior Circumflex Arterj- 

 Deltoid 



Subscapular Arterj' 

 Musculo-cutaneous Nerve 

 Cephalic Vein 

 Thoracic Axis 

 Pectoralis Minor 



ao 19 18 17 16 



12 Pectoralis Major (Clavicular 



Portion) 



13 Subclavius 



14 PectoralLs Major (Sterno- 



costal Portion) 



15 Long Thoracic Artery 



16 Serratus Magnus 



17 Posterior Thoracic Nerve 

 iS Long Subscapular Nerve 

 19 Subscapolaris 



ao Lower Subscapular Nerve 



21 Dorsalis Scapulae Artery 



22 Intercosto-humeral Nerve 



23 Axillary Vein 



24 Latissimus Dorsi 



25 Teres Major 



26 Nerve of Wrisberg 



27 Ulnar NeiA-e 



28 Axillarj- Artery 



29 Median Nerve 



30 Internal Cutaneous Nerve 



Fig. 177. — The Axillary Space. 

 (The Pectoralis Major has been in great part removed.) 



the axillary sheath, and the posterior thoracic and internal anterior 

 thoracic nerves lie behind it. Externally, and above it, are the 

 three cords of the brachial plexus. Internally, and slightly over- 

 |lapping it, is the axillary vein. 



Second Part. — The second part lies under cover of the pectoralis 

 minor, and it is about i^ inches long. 



I Relations. — Anteriorly it is covered by the integument, and the 

 pectoralis major and minor muscles. Posteriorly is the posterior cord 



