98 SURGICAL ANATOMY OF 



anastomosing directly with the dorsalis scapulae of the 

 axillary, on the dorsum scapulae. The internal mam- 

 mary trunk of the subclavian anastomoses with the 

 acromio-thoracic, long thoracic, and subscapular, and the 

 superior intercostal with the superior thoracic. 



SUKGICAL ANATOMY OF THE INNOMINATA. 



Although the innominate, anatomically speaking, be- 

 longs to the thorax, yet any surgical proceeding in con- 

 nection with it would be attempted in the lower part of the 

 carotid region ; hence it has been thought advisable to 

 introduce it into the surgical anatomy of the neck. 



In the neck it, normally, ascends obliquely in the right 

 side to the posterior aspect of the sterno-clavicular articu- 

 lation, where it divides into the right subclavian and 

 common carotid arteries, and is about an inch, or rather 

 more, in length. 



Relations. From before backwards the structures 

 covering it are skin, fascia, some fibres of platysma, 

 and descending branches of cervical plexus, sternal origin 

 of sterno-mastoid, a portion of the manubrium sterni, 

 origins of the sterno-hyoid and sterno-thyroid muscles, 

 remains of thymus gland, left innominate, and right in- 

 ferior thyroid veins, and cardiac branches of vagus. 



On its right side lie the right innominate vein, vagus, 

 and pleura ; on its left, the remains of the thymus gland, 

 and commencement of the left common carotid ; and 

 behind it is the trachea. It occasionally divides higher 

 in the neck than at the sterno-clavicular articulation, and 

 may be seen pulsating. Its position must be carefully 

 made out in performing tracheotomy, particularly in 

 children, where the space in which the operation is feasi- 

 ble is very limited, and the structures so close together, 



