Nerves and Blood Vessels in the Root of the Neck
Anatomically, the root of the neck is the area where the neck attaches to the thorax (the part of the trunk between the neck and the abdomen, including the chest). It’s home to several important nerves and blood vessels that pass between the head, neck, thorax, and upper extremities.
Quite a few nerves reside in the root of the neck:
Vagus nerves: These cranial nerves travel in the carotid sheath with the internal jugular vein and common carotid arteries before moving into the thorax.
Phrenic nerves: These nerves arise from the 3rd, 4th, and 5th cervical nerves and descend into the thorax to innervate the diaphragm.
Here are the main arteries in the root of the neck:
Brachiocephalic trunk: This artery branches off the arch of the aorta just behind the manubrium. It moves to the right and divides into the right common carotid and right subclavian arteries.
Right and left subclavian arteries: The right subclavian branches off the brachiocephalic trunk, and the left subclavian starts from the arch of the aorta. Both arteries have several branches:
The vertebral artery runs through the foramina of the transverse processes of the first six cervical vertebrae.
The internal thoracic artery runs into the thorax.
The thyrocervical trunk has several branches: the suprascapular artery, which supplies blood to the muscles on the back of the scapula, and the cervicodorsal trunk, which branches off into the dorsal scapular and superficial cervical arteries (sometimes the dorsal scapular artery branches off the subclavian artery). The dorsal scapular artery supplies the levator scapulae and rhomboid muscles of the upper back. The inferior thyroid artery also stems from the thyrocervical trunk. It supplies blood to the thyroid and parathyroid glands and the larynx, plus it sends blood to muscles of the neck.
The costocervical trunk gives rise to superior intercostal and deep cervical arteries.
Veins accompany the arteries in the root of the neck. They return blood to the heart from the head:
External jugular vein: This vein drains blood from the scalp and face and empties into the subclavian vein lateral to the internal jugular vein.
Anterior jugular vein: This vein drains blood from superficial submandibular veins and drains to the external jugular vein or the subclavian vein.
Left and right anterior jugular veins: These two veins join to form the jugular venous arch.
Subclavian vein: This vein begins near the 1st rib and joins the internal jugular vein in the anterior cervical triangle where it forms the brachiocephalic vein. This area is called the venous angle.