1356 



CLINICAL AND TOPOGRAPHICAL ANATOMY 



the common carotid corresponding, as far as the upper border of the thyreoid 

 with a hne drawn from the sterno-clavicular joint to midway between the mastoid 

 process and the angle of the jaw. The artery can be best compressed above the 

 level of the cricoid, as here it is less deeply covered. The student should recall 

 the deep relations of the sterno-mastoid, which he may classify as vessels nerves 

 muscles glands and bones; or, according to their position, (1) those above the 

 level of the angle of the jaw; (2) those between the angle of the jaw and the omo- 

 hyoid; (3) those below the omo-hyoid. 



Of the two heads of the sterno-mastoid, the sternal is the thicker and more prominent the 

 clavicular the wider. A stab through the interval which lies between the two heads might 

 wound the bifurcation of the innominate on the right side, and the common carotid on the left 

 the internal jugular, vagus, and phrenic veins, according to the direction of the wound. 



Fig. 1100.— Thymus Gland in a Child at Birth. 



Hyoid bone 



Hyo-thyreoid membrane 



Thyreoid cartilage |"-^(!^ 



Sterno-thyreoid muscle 



Crico-thyreoid 

 membrane 

 Crico-thyreoid muscle 



Thyreoid gland 



Right common carotid 

 artery 



Right vagus nerve 



Right internal jugular 

 vein 



Level of sternum 

 Section of clavicle 

 Section of first rib 



Section of sternum 



--^ Thyreo-hyoid muscle 



I Jil'iLateral portion crico- 

 thyreoid membrane 

 Omo-hyoid muscle 



Sterno-mastoid 

 muscle 



Cricoid cartilage 

 First ring of trachea 



Trachea 



V — Left suspensory 

 \ ligament 

 \ Left recurrent nerve 



(Esophagus 



Left innominate vein 



Left lobe of thymus 



Left internal mammary 

 artery 



Left lung 



Pericardium 



Section of fifth costal 

 cartilage 



Xiphoid process 



I he anterior jugular, commencing in branches from the submaxillary and 

 submental regions, descends at hrst in the superficial fascia between the middle 

 line anrl anterior border of sterno-mastoid, perforates the deep fascia just above 

 the clavicle here entering Burns's space (p. 1361); it then curves laterally to 

 pass beneath both origins of the sterno-mastoid a little above the clavicle, to end 

 usually in the external jugular. ' 



rnn«^l^''" (Jistonded, a large conununi(.itii.g brunch between it and the common facial, which 

 for rr rmrv^nU^"^'"'!"'' ^^'^^."^ ^''^ Hterno-mastoid, must always bo remembered in operatiins 

 for removal of gmnds, etc. The varying level at wliich the external jugular crosses the lateral 



