The middle cervical ganglion is the smallest of the three cervical sympathetic ganglia (i.e. of the cervical portion of the

sympathetic trunk The sympathetic trunk (sympathetic chain, gangliated cord) is a paired bundle of nerve fibers that run from the base of the skull to the coccyx. It is a major component of the sympathetic nervous system. Structure The sympathetic trunk lies just ...

). It presumably represents the merging of the

sympathetic ganglia The sympathetic ganglia, or paravertebral ganglia, are autonomic ganglia of the sympathetic nervous system. Ganglia are 20,000 to 30,000 afferent and efferent nerve cell bodies that run along on either side of the spinal cord. Afferent nerve cel ...

of cervical segments C5–C6. It is usually situated at the level of the sixth

cervical vertebra In tetrapods, cervical vertebrae (: vertebra) are the vertebrae of the neck, immediately below the skull. Truncal vertebrae (divided into thoracic and lumbar vertebrae in mammals) lie caudal (toward the tail) of cervical vertebrae. In sauropsid s ...

Anatomy

The middle cervical ganglion is presumed to represent the union of the two

corresponding to cervical segments C5–C6 since its gray rami communicantes usually join the

cervical spinal nerves In anatomy, cervical is an adjective that has two meanings: # of or pertaining to any neck. # of or pertaining to the female cervix: i.e., the ''neck'' of the uterus. *Commonly used medical phrases involving the neck are **cervical collar **cervic ...

C5–C6, however, the ganglion sometimes also contributes gray rami communicantes to spinal nerves C4 and C7.

Relations

The ganglion is usually situated at the level of the sixth

, lying medial to its carotid tubercle. It is situated either anterior or superior to the

inferior thyroid artery The inferior thyroid artery is an artery in the neck. It arises from the thyrocervical trunk and passes upward, in front of the vertebral artery and longus colli muscle. It then turns medially behind the carotid sheath and its contents, and a ...

. It may adjoin the

inferior cervical ganglion 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 ...

Branches

* Gray rami communicantes – join the anterior rami of the cervical nerves C5–C6, sometimes also C4 and C7. * Thyroid branches – pass alongside the

to the thyroid gland. * Middle cardiac nerve – descends through the neck to reach the cardiac plexus in the thorax.

Variation

It is sometimes absent, having either fused with the

superior cervical ganglion The superior cervical ganglion (SCG) is the upper-most and largest of the cervical sympathetic ganglia of the sympathetic trunk. It probably formed by the union of four sympathetic ganglia of the cervical spinal nerves C1–C4. It is the only ...

or become replaced by small ganglia within the

References

External links