THE CERVICAL NERVES 



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The right nerve is situated more deeply, and is shorter and more vertical in 

 direction than the left; it lies lateral to the right innominate vein and superior 

 vena cava. 



The left nerve is rather longer than the right, from the inclination of the heart 

 to the left side, and from the diaphragm being lower on this than on the right side. 

 At the root of the neck it is crossed by the thoracic duct ; in the superior mediastinal 

 cavity it lies between the left common carotid and left subclavian arteries, and 

 crosses superficial to the vagus on the left side of the arch of the aorta. 



ANTERIOR PRIMARY 



DIVISION OF, 



FOURTH CERVICAL 



BRACHIAL 

 PLEXUS 



PHRENIC 



INFERIOR 

 CERVICAL 

 GANGLION 



INFERIOR 



LARYNGEAL 



NERVE; TO 

 SUBCLAVIUS 



MUSCLE 



COMMUNICATING 



BRANCH FROM 

 BRACHIAL PLEXUS 



THORACIC CARDIAC 

 BRANCH OF 

 VAGUS 

 INFERIOR 

 LARYNGEAL 

 ANTERIOR 

 PULMONARY 



PERICARDIAL 

 BRANCH 



RAMIFICATIONS 

 OF PHRENiC 



FIG. 806. The phrenic nerve and its relations with the vagus nerve. 



Each nerve supplies filaments to the pericardium and pleura, and at the root 

 of the neck is joined by a filament from the sympathetic, and, occasionally, by 

 one from the ansa hypoglossi. Branches have been described as passing to the 

 peritoneum. 



From the right nerve, one or two filaments pass to join in a small phrenic ganglion 

 with phrenic branches of the celiac plexus; and branches from this ganglion are 

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