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The arteries
joins the corresponding artery before passing back to the suprascapular
• The subclavian artery (p. 135): on the right side, from the brachio-
notch. For further details, see Chapter 30.
cephalic artery and, on the left, directly from the arch of the aorta. It
arches over the apex of the lung and crosses the 1st rib in a shallow into the axilla. The suprascapular nerve arises from the upper trunk and
• The phrenic nerve: is formed by branches from the 3rd, 4th and 5th
groove, which it shares with the lower trunk of the brachial plexus (mainly the 4th) cervical nerves and descends on the anterior surface of
(Fig. 63.2). At the outer border of the 1st rib it becomes the axillary scalenus anterior before crossing the subclavian artery and entering the
artery. It has five branches (p. 135): thorax.
• The vertebral artery. • The vagus nerve: this crosses the subclavian artery and descends
• The internal thoracic artery. into the thorax. On the right side it gives off the right recurrent laryn-
• The thyrocervical trunk. geal nerve which hooks under the artery and ascends, deep to the com-
• The costocervical trunk. mon carotid, to reach the larynx. The left recurrent laryngeal, having
• The dorsal scapular artery. arisen in the thorax, runs upwards between the trachea and oesophagus.
• The sympathetic trunk: descends close to the vertebral artery. The
The veins middle cervical ganglion is close to the entry of the artery into the fora-
• The subclavian vein: begins at the outer border of the 1st rib and lies men transversarium of C6 and the inferior cervical ganglion is near the
in a shallow groove on the upper surface of the rib in front of scalenus neck of the 1st rib behind the origin of the vertebral artery. It may be
anterior. At the medial border of this muscle it is joined by the internal fused with the 1st thoracic ganglion to form the stellate ganglion.
jugular vein to form the brachiocephalic vein. The internal jugular vein
is enclosed in the carotid sheath, along with the common carotid artery The thoracic duct (Fig. 63.1)
and the vagus nerve. Other veins entering it accompany the small arter- On the left side only. The duct ascends out of the thorax between the
ies but the inferior thyroid veins are solitary and run down from the trachea and oesophagus and arches laterally between the carotid sheath
lower border of the thyroid gland, in front of the trachea, to reach the in front and the vertebral artery behind. It ends by joining the junction
left brachiocephalic vein in the thorax. between the internal jugular and subclavian veins.

The nerves
• The upper, middle and lower trunks of the brachial plexus:
emerge from between the scalenus anterior and medius and pass down

The root of the neck 141