The costocervical trunk arises from the superior and posterior part of the second part of subclavian artery, behind the scalenus anterior on the right side, and medial to that muscle on the left side.
Passing backward, it splits into the deep cervical artery and the supreme intercostal artery (highest intercostal artery), which descends behind the pleura in front of the necks of the first and second ribs, and anastomoses with the first aortic intercostal (3rd posterior intercostal artery).
The inferior cervical ganglion is one of the three cervical sympathetic ganglia (i.e. of the cervical portion of the sympathetic trunk). It is situated between the base of the transverse process of the last cervical vertebra and the neck of the first rib, on the medial side of the costocervical artery.
It is often united with the first (and sometimes the second) thoracic ganglion to form the cervicothoracic ganglion (stellate ganglion).
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