The inferior cervical ganglion is situated between the base of the transverse process of the last

cervical vertebra In tetrapods, cervical vertebrae (singular: 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 sau ...

and the neck of the

first rib The rib cage, as an enclosure that comprises the ribs, vertebral column and sternum in the thorax of most vertebrates, protects vital organs such as the heart, lungs and great vessels. The sternum, together known as the thoracic cage, is a semi-r ...

, on the medial side of the

costocervical artery The costocervical trunk arises from the upper and back part of the second part of subclavian artery, behind the scalenus anterior on the right side, and medial to that muscle on the left side. Passing backward, it splits into the deep cervical ...

. Its form is irregular; it is larger in size than the

middle cervical ganglion The middle cervical ganglion is the smallest of the three cervical ganglia, and is occasionally absent. It is placed opposite the sixth cervical vertebra, usually in front of, or close to, the inferior thyroid artery. It sends gray rami communican ...

, and is frequently fused with the first

thoracic ganglion The thoracic ganglia are paravertebral ganglia. The thoracic portion of the sympathetic trunk typically has 12 thoracic ganglia. Emerging from the ganglia are thoracic splanchnic nerves (the cardiopulmonary, the greater, lesser, and least splanc ...

, under which circumstances it is then called the "

stellate ganglion The stellate ganglion (or cervicothoracic ganglion) is a sympathetic ganglion formed by the fusion of the inferior cervical ganglion and the first thoracic (superior thoracic sympathetic) ganglion, which exists in 80% of people. Sometimes, the seco ...

Structure

It is connected to the middle cervical ganglion by two or more cords, one of which forms a loop around the

subclavian artery In human anatomy, the subclavian arteries are paired major arteries of the upper thorax, below the clavicle. They receive blood from the aortic arch. The left subclavian artery supplies blood to the left arm and the right subclavian artery supplie ...

and supplies offsets to it. This loop is named the ''ansa subclavia'' (Vieussenii). The ganglion sends

gray rami communicantes Each spinal nerve receives a branch called a gray ramus communicans (plural rami communicantes) from the adjacent paravertebral ganglion of the sympathetic trunk. The gray rami communicantes contain postganglionic nerve fibers of the sympathetic ne ...

to the seventh and eighth cervical nerves.

Branches

The inferior cervical ganglion gives off two branches: * The

Inferior cardiac nerve The inferior cardiac nerve arises from either the inferior cervical or the first thoracic ganglion. It descends behind the subclavian artery and along the front of the trachea, to join the deep part of the cardiac plexus. It communicates freely ...

* ''offsets to bloodvessels'' form plexuses on the subclavian artery and its branches. The plexus on the

vertebral artery The vertebral arteries are major arteries An artery (plural arteries) () is a blood vessel in humans and most animals that takes blood away from the heart to one or more parts of the body (tissues, lungs, brain etc.). Most arteries carry o ...

is continued on to the basilar,

posterior cerebral The posterior cerebral artery (PCA) is one of a pair of cerebral arteries that supply oxygenated blood to the occipital lobe, part of the back of the human brain. The two arteries originate from the distal end of the basilar artery, where it bifur ...

, and

cerebellar arteries A cerebellar artery is an artery that provides blood to the cerebellum. Types include: * Superior cerebellar artery * Anterior inferior cerebellar artery * Posterior inferior cerebellar artery The posterior inferior cerebellar artery (PICA) is ...

. The plexus on 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 als ...

accompanies the artery to the

thyroid gland The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans it is in the neck and consists of two connected lobe (anatomy), lobes. The lower two thirds of the lobes are connected by a thin band of Connective tissue, tissue cal ...

, and communicates with the recurrent and

external laryngeal nerves The superior laryngeal nerve is a branch of the vagus nerve. It arises from the middle of the inferior ganglion of vagus nerve and in its course receives a branch from the superior cervical ganglion of the sympathetic nervous system. The super ...

, with the

superior cardiac nerve The superior cardiac nerve arises by two or more branches from the superior cervical ganglion, and occasionally receives a filament from the trunk between the first and second cervical ganglia. It runs down the neck behind the common carotid arte ...

, and with the plexus on the

common carotid artery In anatomy, the left and right common carotid arteries (carotids) (Entry "carotid"
in
Cervical spine In tetrapods, cervical vertebrae (singular: 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 sau ...

External links

* - "The Sympathetic Trunk and Cervical Ganglia" {{Authority control Autonomic ganglia