The stellate ganglion is a collection of nerve cell bodies arising from the fusion of two ganglia of the sympathetic border cord. Sympathetic nerve fibers branch off from the ganglion to the head, neck, arm, heart, and lungs. The stellate ganglion is used in stellate blockade for therapeutic release of venous spasm.
What is the stellate ganglion?
Nerve ganglia of the peripheral nervous system are called ganglia. These ganglia are collections of nerve cell bodies that appear as thickenings. Ganglia act as a switching point for different nerves and again serve other nerve structures on the way to their target regions as a mere transit station. The ganglion of the lower neck region is referred to in technical terminology as the cervical inferior ganglion. This collection of nerve cell bodies often enters into a fusion with the first thoracic ganglion. A fusion of this type is referred to by physicians as the cervicothoracic ganglion or stellate ganglion. Nerve pathways such as the subclavian ansa, vertebral nerve, subclavian plexus, and inferior cardiac cervical nerve lead out of this ganglion. The nerve node is located on the caput costae at the first rib and thus lies posterior to the pleural dome and between the vertebral and common carotid arteries. The collection of nerve cell bodies is part of the autonomic nervous system and therefore, with its individual pathways, eludes voluntary control. Consisting of sympathetic and antagonistic parasympathetic nervous systems, the autonomic nervous system is involved in the control of all automatically occurring bodily functions.
Anatomy and structure
The stellate ganglion consists of the fusion of two sympathetic border ganglia. The lowest cervical ganglion fuses in structure with the first to second thoracic ganglion. The sympathetic fibers of the ganglion run in all directions, giving the nerve node a star-like shape. The nerve cell body cluster is located lateral to the first thoracic vertebra and receives its nervous influxes from axons whose cell bodies are located within the gray matter of the spinal cord. These axons enter the border cord by means of the rami communicantes albi on the spinal nerves. Several nerve tracts lead away from the nerve node. The ansa subclavian nerve cord loops around the subclavian artery to draw to the cervical medium ganglion. At this point, the sympathetic trunk runs toward the cervical superior ganglion, which handles its switching to postganglionic nerve fibers. The vertebral nerve also continues from the stellate ganglion. With the artery of the same name, this nerve travels to the sixth cervical vertebra, passes through the transverse process canal, and sends sympathetic fibers to the cervical nerves. The subclavian plexus of the stellate ganglion consists of nerve fibers that travel with the subclavian artery toward the anterior superior aspect of the limb. In addition, the inferior cardiac nerve runs from the stellate ganglion to the cardiac plexus at the base of the heart.
Function and Tasks
Like all ganglia, the stellate ganglion performs the function of a through station as well as an interconnecting station. Sympathetic fibers branch off from the ganglion to the head, neck, arms, as well as the heart and lungs. Not all of them are switched. Some pass through the ganglion without switching. The stellate ganglion is a purely sympathetic ganglion formed by two ganglia of the sympathetic border cord. The sympathetic nervous system is the antagonist of the parasympathetic nervous system. While the parasympathetic tends to have a relaxing effect on the body, the sympathetic is associated with peak physical performance. From an evolutionary-biological point of view, the sympathetic part of the autonomic nervous system is supposed to ensure survival in stressful and extreme situations by directing the body towards peak performance. The acceleration of the heartbeat is associated with the sympathetic nervous system, as is the dampening of all currently dispensable bodily functions. More energy is available for the central and vital activities of the organism due to increased sympathetic activity. Especially the ganglion stellatum carries relevant nerve branches of the sympathetic nervous system in this respect, which radiate to the heart and lungs and adapt the organism to stress situations with their stimulating influence on the activities of these two organs.Outside of stress situations, there is an interplay between parasympathetic and sympathetic fibers. The parasympathetic portion attenuates the sympathetic influence on the cardiopulmonary circulation thus to the resting state as long as there is no stress situation.
Diseases
The stellate ganglion plays a role in clinical practice primarily in the context of stellate blockade. In this targeted local conduction anesthesia, the stellate ganglion, including all nerves that pass through it, is switched off for a certain period of time. This procedure is used for arterio-venous spasms (vasospasms). The spasm is relieved by the blockade because the blood vessels carry sympathetic innervation. By blocking the stellate ganglion, only the parasympathetic influence on the vessels prevails. This results in relaxation of the vascular musculature, also known as vasodilation. Signs of successful anesthesia of the ganglion include Horner’s syndrome symptoms consisting of miosis, ptosis, and enophthalamus. Stellate blockade can also be used for migraine or hemiplegic headache. The same applies to complaints of craniocerebral trauma, osteochondrosis symptoms of the cervical spine, periarthritis of the shoulder joint or painful trigeminal as well as zoster neuralgia. In addition, the stellate ganglion can be surgically eliminated. This procedure is the last resort in the treatment of patients with Raynaud’s disease. Raynaud’s disease is characterized by spasmodic narrowing of the blood vessels in the fingers and toes. The nose or ears may also be affected by the vasospasms.
