Middle cervical ganglion

Middle cervical ganglion is the smallest of all cervical ganglia. It is situated inside the cervical sympathetic trunk in the region of the sixth cervical vertebrae C6.

The middle cervical ganglion receives preganglionic sympathetic neurons from the lateral gray horns of the upper thoracic spinal segments. These pre-ganglionic neurons travel an extra-long distance by ascending in the sympathetic trunk to reach the middle cervical ganglion. Here they synapse with cell bodies of postganglionic sympathetic neurons, which in turn, get distributed to various regions of the head and neck and mediastinum via the following routes:

• Post-ganglionic neurons reach out to the ventral rami of C5 and C6 cervical spinal nerves, through gray rami communicantes,

• Some post-ganglionic neurons wind around inferior thyroid artery to innervate structures including esophagus, pharynx, trachea and larynx,

• Lastly, post-ganglionic neurons reach out to the cardiac plexus via superior cardiac nerves, to innervate the heart.

Superiorly, the middle cervical ganglion is connected with the superior cervical ganglion, while inferiorly with the inferior cervical ganglion, via interganglionic branches as part of the sympathetic trunk.

The middle cervical ganglion receives arterial blood supply from either the ascending pharyngeal or the inferior thyroid artery–both branch of external carotid artery–while the venous drainage is via the internal jugular vein.