| Inferior cervical ganglion | |
| Latin: | ganglion cervicale inferius |
| Innervates: | Thyroid |
The inferior cervical ganglion is one of the three cervical sympathetic ganglia (i.e. of the cervical portion of the sympathetic trunk).[1] 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[2]) thoracic ganglion to form the cervicothoracic ganglion (stellate ganglion).[3]
The inferior cervical ganglion is irregularly shaped. It is substantially larger than the middle cervical ganglion (but smaller than the superior cervical ganglion). As the sympathetic trunk curves posteriorly between the neck and thorax, this ganglion is oriented in a nearly anteroposterior axis.
The ganglion is presumed to represent the union of the cervical segmental sympathetic ganglia C7-C8 and the thoracic segmental sympathetic ganglia T1, but sometimes up to T4 as well - the T1 ganglion may or may not be separate to leave a distinct inferior cervical ganglion. The gray rami communicantes of the inferior cervical ganglion join the cervical nerves C7-C8.
The ganglion is situated posterior to the commencement of the vertebral artery.
The inferior cervical ganglion and middle cervical ganglion are connected by two (an anterior one and a posterior one) or more highly variable cords. The posterior cord typically splits to surround the vertebral artery; the anterior cord loops around the subclavian artery, forming the ansa subclavia.
The inferior cervical ganglion gives off two branches:
It is probably formed by the coalescence of two ganglia which correspond to the seventh and eighth cervical nerves.