642 



THE BLOOD-VASCULAR SYSTEM 



clavicular articulation on the left side to the lower border of the first costal carti- 

 lage at its junction with the sternum on the right side, will indicate its course. 

 The left innominate vein is on a level with the top of the sternum at birth. 



Relations. — In front, in addition to the manubrium of the sternum, it has the origins of 

 the sterno-hyoid and sterno-thyreoid muscles, and the remains of the thymus gland, the sternal 

 end of the left clavicle, and the sterno-clavicular articulation. 



Behind are the three chief arteries arising from the arch of the aorta, the trachea, and the 

 left phrenic and left vagus nerves. 



Below it is the arch of the aorta. 



Above it are the cervical fascia, the inferior thyreoid, and thyreoidea ima veins. 



Tributaries. — In addition to the internal jugular and subclavian veins, by the 

 confluence of which the innominate veins are formed, each vein receives on its 

 upper aspect the vertebral, the deep cervical, and inferior thyreoid veins; and 



Fig. 509.— The 

 (Modified from 

 Internal jugular vein' 

 Transverse cervical 



Transverse scapiilar 

 artery 



Right recurrent nerve 



Right common carotid 

 artery 



Subclavian vein 



Vagus nerve 



Innominate artery "Z''^ ^ 



Left innominate vein "^ 



Phrenic nerve 



Superior vena cava 



Arch of aorta 



Right bronchus 



Branch of right pul- 

 monary artery 



Branch of right pul- 

 monary vein 



Right pulmonary 

 artery 

 Branch of right pul- 

 monary artery 



Branch of right pul- 

 monary vein 



Right atrium 



Right coronary artery 

 Thoracic vertebra 



Azygos vein 



Intercostal veins 



Intercostal arteries 



Vena Cava Superior and the Innominate Veins. 

 a dissection in St. Bartholomew's Hospital Museum.) 



Inferior thyreoid 



Thyreoid gland 



Left internal jugular 



vein 

 Vagus nerve 



Left common carotid 



artery 

 Left recurrent 

 nerve 



Left subclavian artery 



Left subclavian vein 

 Left internal mammary 



vein 

 Left superior inter- 

 costal vein 



Phrenic nerve 



Vagus nerve 



Recurrent nerve 



Ligamentum arteri- 

 osum 



Left pulmonary artery 

 Left pulmonary vein 



Left bronchus 

 Branch of left pulmon - 

 ary artery 



Pulmonary artery 

 Left pulmonary vein 



Left coronary artery 



Conus arteriosus 



(Esophagus 

 Thoracic duct 

 Thoracic aorta 



on its lower aspect the internal mammary vein. The left vein, moreover, is 

 joined by the thyreoidea ima, the left superior intercostal, and by the thymic, 

 tracheal, oesophageal, superior phrenic, anterior mediastinal, and pericardiac veins. 

 At the confluence of the internal jugular and subclavian veins on the right side 

 the three lymphatic trunks or the right lymphatic duct open; on the left side the 

 thoracic duct. 



TEE VEINS OF THE HEAD AND NECK 



The veins of the head and neck may be divided for purposes of description into 

 the superficial, wiiich return the blood from the external parts of the head and 



