Costocervical trunk

At a glance

English

Costocervical trunk

Latin (TA2)

Truncus costocervicalis

System

Artery

Region

Trunk

Side

Paired, left and right

About the costocervical trunk

The costocervical trunk is a short arterial stem that comes off the upper and posterior surface of the subclavian artery. On the right it usually arises from the second part of the subclavian, behind scalenus anterior; on the left it more often comes from the first part, just medial to that muscle. It is one of the smaller subclavian branches, alongside the vertebral artery, internal thoracic artery, thyrocervical trunk and dorsal scapular artery.

From its origin the trunk curves backwards over the cervical pleura, the dome of the lining of the lung, towards the first rib's neck. There it splits into its two branches. The deep cervical artery continues backwards above the eighth cervical nerve, between the seventh cervical transverse process and the first rib, and climbs the back of the neck between the semispinalis muscles. The supreme (highest) intercostal artery turns downwards anterior to the necks of ribs one and two, behind the pleura.

As it crosses the first rib's neck, the supreme intercostal lies between the cervicothoracic (stellate) ganglion of the sympathetic trunk on its medial side and the anterior ramus of the first thoracic nerve on its lateral side. It gives the posterior intercostal artery of the first space and usually that of the second, which run like the lower intercostal arteries; the second often joins a branch from the first aortic intercostal (the third posterior intercostal artery). Each of these gives a posterior branch to the deep back muscles and a spinal branch through the intervertebral foramen to the spinal cord and its coverings.

The trunk sits close to the lung apex and the stellate ganglion, which matters in operations on the subclavian artery and thoracic outlet. Its branches also form collateral routes between the subclavian artery and the aorta, which can enlarge when the aorta is narrowed in coarctation.

Course and supply

Arises from

Leaves the upper posterior surface of the subclavian artery: usually its second part on the right, behind scalenus anterior, and its first part on the left.

Ends in

Divides near the first rib's neck into the supreme intercostal and deep cervical arteries.

Supplies

Through its branches supplies the deep muscles of the back of the neck, the first one or two intercostal spaces, the upper deep back muscles and the upper thoracic spinal canal.