The blood flows to the brain through two arterial systems:
The dividing line between the Anterior and Posterior circulation of the brain is the Posterior Communicating Arteries.
The diameter of the blood vessels is controlled by post-ganglionic sympathetic efferent neurons (1). As a rule, increased sympathetic neuronal firing causes vasoconstriction, reducing target blood delivery. Mechanical irritation to the sympathetic neurons causes increased sympathetic firing and vasoconstriction.
The pre-ganglionic sympathetic efferent cell bodies arise from the intermediolateral column of the spinal cord (1). However, reference texts from a century ago (1916, 1921) indicated that these pre-ganglionic sympathetic cell bodies arose only from spinal levels T1-L2 (2, 3). However, in 1960, Eugene Neuwirth, MD, published a study in the journal Lancet titled (4):
Current Concepts of the Cervical Portion of the Sympathetic Nervous System
In this article, Dr. Neuwirth, a specialist in physical medicine, rehabilitation, and rheumatic diseases, discusses “current” evidence, that in 1940, French researchers showed that pre-ganglionic sympathetic neurons are found at the spinal cord levels of C4, C5, C6, C7, and C8. This was confirmed in 1947.
The pre-ganglionic sympathetic neurons synapse with the post-ganglionic sympathetic neurons in the three cervical sympathetic ganglia (superior, middle, and inferior or stellate ganglion). These cervical ganglia are “visceral ganglia,” as the “efferent rami proceed to the viscera in the neck and the chest.”
Dr. Neuwirth presents evidence indicating that the cervical post-ganglionic sympathetic neurons:
Dr. Neuwirth also presents evidence that the vertebral arteries (to the neck and head), the carotid arteries (to the neck and head), and the subclavian arteries (to the upper extremities/shoulders) are controlled by sympathetic innervation derived from preganglionic cell bodies from the cervical spine, C4-C8.
Dr. Neuwirth notes that “disco-vertebral disease, may engender preganglionic stimulation or over-activity,” inducing vasoconstriction in certain arteries with resultant:
In 1925 and 1928 respectively, Jean Alexandre Barre, MD, a French neurologist, and Yong-Choen Lieou, a Chinese physician, each independently described a syndrome with a variety of symptoms thought to be due to a dysfunction in the posterior cervical sympathetic nervous system (the post-ganglionic sympathetic efferents that travel with the vertebral artery). The posterior cervical sympathetic syndrome became known as Barre-Lieou Syndrome.
The Barre-Lieou Syndrome is a commonly missed source of chronic pain. Classic Barre-Lieou symptoms include neck pain, blurred vision, nausea, vertigo, and tinnitus. Other symptoms include:
These symptoms may also be reported:
Both Barre and Lieou attributed these symptoms to irritation or injury with increased firing of the posterior cervical sympathetic neurons. The posterior cervical sympathetic system consists of the following:
In 1954, physicians Louis Gayral, MD, and Eugene Neuwirth, MD, published a study in the New York State Journal of Medicine titled (5):
Oto-neuro-ophthalmologic Manifestations of Cervical Origin:
Posterior Cervical Sympathetic Syndrome of Barre-Lieou
In this article, Drs. Gayral and Neuwirth note that the posterior cervical sympathetic system consists of the network of post-ganglionic sympathetic neurons surrounding the vertebral artery, known as the vertebral nerve. The vertebral nerve controls the diameter of the vertebral artery, and ascends with it into the head.
Gayral and Neuwirth note that the vertebral nerve can be irritated or injured as a consequence of neck injury and/or cervical spine spondylosis. “Osteoarthritis of the cervical portion of the vertebral column was found to be the most frequent single etiologic factor underlying the posterior cervical sympathetic syndrome.” Additionally, common sources of the vertebral nerve irritation are uncinate process arthrosis, facet spondylosis, and pathology of the articular capsules and ligaments. The resultant Barre-Lieou Syndrome is often characterized by bizarre symptoms that are often interpreted as being psychological, but they are actually subsequent to “damaged anatomic structures in the cervical region.”
Post-ganglionic sympathetic efferent neurons (vertebral nerve) not only control the diameter of the vertebral arteries, but also the “basilar artery and its branches, including the internal auditory artery.” The symptoms of Barre-Lieou “may manifest by pain in almost any part of the head or neck”:
There are few objective findings in the Barre-Lieou Syndrome. “In contrast to the abundance of symptoms, there is a paucity of objective signs.” The neck muscles are often painful and show sustained contraction; one or more of the facial muscles may be in spasm. Posterior and lateral neck muscles show sustained and painful spasm.
These authors state:
Lesions in the cervical spine can irritate elements of the posterior cervical sympathetic system and thus “provoke vasoconstriction in the vertebrobasilar vascular tree. The vasoconstriction reduces the caliber of the intracranial vessels supplied by the posterior sympathetic system and thus restricts the blood flow in them.”
“In view of the fact that the lateral part of the bulbo-pontine region is supplied by arteries of a very small caliber, called ‘short circumferential arteries,’ circulation disturbances will lessen their blood supply with consequent effect on the lateral part of the bulbo-pontine region which is the site of the nuclei of the fifth, sixth, seventh, eighth, ninth, tenth and eleventh cranial nerves. Restriction of the flow of blood to the region containing the nuclei of these cranial nerves could be responsible for the production of the symptoms and signs of the syndrome of Barre-Lieou. The syndrome, therefore, could be called the syndrome of the short circumferential arteries.”
Gayral and Neuwirth note that the most frequent x-ray finding in the Barre-Lieou Syndrome is loss of cervical lordosis. Other findings include:
These authors note several treatment approaches that are helpful for those suffering from this syndrome, including:
The following year (1955), Dr. Akos Kovacs, from the Roentgen Department of Rokus Hospital, Budapest, Hungary, published a study in the journal Acta Radiologica titled (6):
Subluxation and Deformation of the Cervical Apophyseal Joints
Dr. Kovacs ascribes the majority of headaches to a posterior subluxation of the cervical vertebrae causing a pressure kink on the vertebral artery by the superior articular process of the vertebrae below. This mechanically compromises vertebral artery blood flow and irritates the plexus of postganglionic sympathetic nerves that travel with the vertebral artery. Importantly, Dr. Kovacs’ description of the “posterior subluxation” is identical to the teachings and descriptions of present day chiropractic. Dr. Kovacs notes that this is the same as the sympathetic syndrome of Barre-Lieou.
Dr. Kovacs supports his perspective using (1) careful x-ray analysis, (2) vertebral artery angiograms, and (3) a careful assessment of post-mortem anatomical specimens.
Immediately behind the vertebral artery are the spinal nerve root and the dorsal root ganglion.
The distance between the anterior facet joint and the posterior aspect of the vertebral artery is 2-3 mm. The distance between the lateral vertebral body and the medial vertebral artery is 3-6 mm. As such, facet arthrosis/osteophytes is more likely to irritate/compress the vertebral artery than is body/uncinate arthrosis/osteophytes.
Dr. Kovacs notes that the “subluxation” is a functional disorder of the facet motion segment. Long-standing subluxation results in compensatory osteophytes. He notes:
“In this paper we shall deal with subluxations of the small joints resulting in constriction or circulatory disturbance in the vertebral artery and impaired function of the plexus [of] sympathetic [nerves that accompany the] vertebral [artery].”
“By subluxation we mean the displacement of contiguous articular surfaces.”
“The upper articular process of the cervical vertebrae frequently becomes dislocated [subluxated] and compresses the vertebral artery and the accompanying sympathetic nerve against the border of the foramen of the transverse process above.”
Dr. Kovacs shows an angiogram noting:
“Vertebrae out of line; subluxation. The articular process reaches the artery and compresses it against the lower border of the transverse process.”
To assess cervical spine “subluxations” and accompanying spondylosis/spondyloarthrosis, the author recommends these x-rays:
Dr. Kovacs notes that cervical vertebral subluxations in the presence of osteophytes increase the incidence of vertebral artery compromise and postganglionic sympathetic nerve irritation. He states:
“Headache might be clue to lesions of the articular processes giving rise to [vertebral] arterial stenosis.”
“Headache radiating from the top of the skull and the nuchal region as well as the upper cervical sympathetic syndrome described by Barre-Lieou is, more frequently produced by pressure exerted on the vertebral artery and nerve by the superior articular process than by other conditions.”
Degenerative “broadening of the [facet] joint surface will, in addition to restricting movement, irritate, and later paralyze, the sympathetic plexus and further interfere with the circulation of the vertebral artery either directly or by producing vasospasm.”
Dr. Kovacs presents a number of case studies in this article. He notes that characteristics of patients afflicted by facet articular process impingement on the vertebral artery and its sympathetic plexus include:
Dr. Kovacs notes that the symptoms associated with this syndrome can be improved by:
“During the manipulation of the neck two loud cracks were heard. They were followed by immediate relief of pain and headache. The manipulation was repeated upon several occasions. The decrease in the intensity of the cracks produced suggested that the reduction was becoming effective, and a fortnight later this was confirmed by roentgenology. The swelling of the joints of the hands had disappeared and after a long period of rest, the patient resumed her occupation. No doubt, the artery was in this case affected by the subluxation of the superior articular processes whilst the nerve root and the accompanying sympathetic plexus were being injured by the dislocation of the superior articular processes.”
“Bilateral or unilateral headaches, as a result of this, may result. These headaches cease while the subluxation is being reduced by anteflexion-traction of the head.”
The most important aspect of this article is that the author uses the word/concept “subluxation” in the exact context of that of traditional chiropractic: a slight malposition of the articular surfaces. The author emphasizes that a slight posterior subluxation of the cervical vertebrae with respect to the vertebrae below will cause a slight compression of the vertebral artery and an irritation to the plexus of postganglionic sympathetic nerves that accompany the artery, resulting in the Barre-Lieou Syndrome. Interestingly, he mentions:
Essentially, when a vertebra subluxates posteriorly, the superior articulating facet of the vertebrae below moves towards the vertebral artery and its plexus of postganglionic sympathetic efferent nerves, irritating or compressing both structures. The correction of the subluxation using spinal manipulation and other adjuncts may bring effective relief to these patients.
The concept of the Posterior Sympathetic Syndrome of Barre-Lieou remains controversial because there are no gold–standard tests to prove its existence. Yet, this syndrome continues to be described in modern scientific literature (7, 8, 9).
“Authored by Dan Murphy, D.C.. Published by ChiroTrust® – This publication is not meant to offer treatment advice or protocols. Cited material is not necessarily the opinion of the author or publisher.”