Neurologic-like symptoms and conditions of Cervical Spine Instability
Ross Hauser, MD
This article is about understanding some of the neurologic-like symptoms that you may be suffering from and tracing the origins of these problems to compression of the nerves, veins, arteries, and the spinal cord by the bones of the neck. In essence, the neurology of cervical spine instability.
In this article, we will focus on some of these symptoms and conditions including:
- Headache and Craniofacial Pain Syndromes
- Cervically Mediated Autonomic Symptoms (Barré-Liéou syndrome)
- Vertigo / Dizziness
- Blurred Vision
- Cardiac Manifestations
- Dysphonia and Voice Hoarseness
- Mast Cell Activation Syndrome
- Whiplash-associated conditions
- Post-concussion syndrome, migraine headaches
- Meniere’s disease
- Cervical spine subluxations
- Postural tachycardia syndrome
- Emotional stress and anxiety (neurologic-like and psychiatric-like).
For many people, it is well understood that their neck problems, cervical spine syndromes, and symptoms are manifest and pinpointed as being caused by their cervical spine instability and hypermobility of the bones of the neck. The conditions of cervical radiculopathy, cervicogenic headache, and cervical myelopathy are perhaps the most well-known. Yet, for many, this connection between cervical spine instability and neurologic-like symptoms is not understood, a diagnosis of cervical spine instability is only made after years of failed treatment, and for some, the diagnosis is not made until after failed surgery. For others, the diagnosis can be missed altogether.
The nerve network that travels from the brain to the body must pass through the neck. The neck then has a super density of vital nerves, specifically in the upper cervical spine. This dense neurologic anatomy of the cervical spine region, specifically the upper segments, in the setting of hidden cervical instability is underappreciated for its role in the development of cranial nerve and autonomically mediated syndromes.
Patients with whiplash injury, hypermobility, Ehlers-Danlos syndrome (specifically to the neck please see our article Ehlers-Danlos Syndrome, Atlanto-axial instability, and Craniocervical instability), Positional Orthostatic Tachycardia Syndrome (POTS), and mast cell activation are of particular need in understanding this close spatial relationship of bone-neural anatomy and how it may impact their daily function and symptomatic manifestations of their dysfunction related to instability.
NOTE: Destabilization of C0-C1 or C1-C2 joints can lead to extremes of upper cervical instability with severe life-threatening neurologic sequelae and consequences that necessitate surgical consult. On several occasions we have stopped a person in the middle of a motion x-ray examination because of how severe the instability was on the exam. People with serious symptoms after head or neck trauma including dysarthria (motor speech disorder), diplopia (double vision), dysphagia (swallowing difficulties), drop attacks, paraesthesias or weakness in the limbs (especially the legs) should seek surgical consultation. If radiographic analysis confirms significant upper cervical instability, then surgical fusion is performed. However, the vast majority of people with a myriad of symptoms do not meet the criteria for surgical fusion.
Neurologic-like symptoms and conditions of Cervical Spine Instability – a problem of ligament damage and laxity
In this section we are going to discuss the cervical spine ligaments and their weakness and laxity as a possible cause of the neurologic-like symptoms that you may be suffering from. We are going to first present research evidence to explain how your neck weakness can be causing the symptoms and conditions highlighted above.
The definition of ligamentous
The word ligamentous refers to the “ligaments.” Ligaments are the strong connective tissue that hold the cervical spine bones in place. “Ligamentous upper cervical instability” refers to damaged, weakened, loose or “lax” ligaments in the C1-C2 region that are no longer strong enough to prevent the upper cervical vertebrae from wandering out of position. “Ligamentous cervical instability” refers to damaged, weakened, loose or “lax” ligaments in the C3-C7 region that are no longer strong enough to prevent the cervical vertebrae from wandering out of position. When the ligaments are no longer strong enough to prevent the bones from sliding on top of each other, the ligaments can then be seen as the main culprit of nerve impingement, herniation of discs, arterial and vein compression, and other challenges that lead to the symptoms and conditions of the neurologic and neurologic-type symptoms that many people we see with a long history of neck problems suffer from.
In our opinion, cervical instability, especially ligamentous upper cervical instability, is the missing structural cause and/or co-morbidity for many chronic disabling symptoms and diagnoses.
The degenerative, acute and hereditary factors in ligament injury.
If you are reading this article it is very likely that you or a loved one is suffering from neurologic and neurologic-type symptoms related to a neck injury. You may be reading this article because your medical history is long, complicated and filled with hopeful treatments, disappointing results, and a doctors not knowing how to further proceed in your case.
You are here at this point because:
- You suffered from an acute injury such as whiplash or other neck injury that damaged the cervical spine ligaments.
- You have had continued neck problems over the years. It may have started with many hours in front of some type of screen or monitor and bad posture at the desk. It may have started with a job that you have that is physically challenging.
- You may be here because it was discovered that you suffer from hEDS or hypermobile Ehlers-Danlos syndrome. You not only have neck issues but it was discovered that your ligament laxity issues extended into most of your joints.
Regardless of why you are here you are seeking the answers to get you to “there.” There is the understanding of what is happening in your cervical spine and the understanding of the most realistic outcome expectations for any treatment.
Understanding neurocatastrophic consequences
The term “neurocatastrophic consequences” sounds scary and it is scary for suffers of the many symptoms that can be caused by cervical spine instability. Again, if you are reading this article, it is very likely that you are already in neurocatastrophic consequences.
Neurocatastrophic consequences have their origin in damage to the cervical supporting structures. When these supporting structures are damaged (a condition known as cervical dysstructure – dysfunction with the cervical spine structure) and the carotid sheath and/or spinal cord and the fluids contained within get compressed, torqued and stretched. (see the image and explanation below).
The two most common mechanisms by which severe symptoms arise are venolymphatic drainage (vein compression and fluid backup) compression leading to intracranial hypertension and alterations of brain function and cervicovagopathy (cervical-induced vagus nerve injury or signal interference) causing dysautonomia and systemic inflammation, both of which lead to dysfunctional body homeostasis.
In addition to the symptoms and conditions already listed, we find that left untreated or improperly treated, cervical spine instability can lead to cardiac arrhythmias, visual loss, cerebral and spinal cord atrophy, drop attacks, unrelenting fatigue, mast cell activation syndrome, dystonic storms and serious digestive issues with threatening weight loss.
The research in understanding this problem.
We have authored many research papers on understanding cervical spine instability. They will be discussed briefly below. To help our understanding of the problem, we also examine the published research of other clinicians and health care investigators.
We are going to start in 1980 and work our way to the present in providing you with an understanding of the discovery of how cervical spine instability may be causing your neurologic-like symptoms.
In 1992, Yale University researcher Dr. Manohar Panjabi wrote an influential paper in the Journal of spinal disorders (1). What he did was lay the groundwork to help explain the neurologic symptoms some people may have. Dr. Panjabi provided a three-subsystem model for spinal stability that divided understanding of stability and instability as the workings of :
- A passive subsystem consisting of vertebrae, discs, and ligaments, (passive stability).
- An active subsystem of paraspinal muscles and tendons, (active stability through movement).
- And the neural subsystem of peripheral nerves with the central nervous system monitors signals, directing the active subsystem as needed. (the nerve communication system which makes stability work or instability not work).
Dr. Panjabi expressed an understanding that the ligament-muscular stabilizing system of the entire spine shows that stimulation of spinal ligaments (via nerve impulse or movement) results in the activation of spinal stabilizers, emphasizing the intimate nature of these subsystems.
Previously in 1980 (2) and again in 1990, Dr. Panjabi teamed with noted Harvard researcher Dr. Augustus A. White III to provide the most widely accepted definition of clinical spine instability: “Clinical instability is the loss of the ability of the spine, under physiologic loads to maintain relationships between vertebrae in such a way that there is neither initial or subsequent damage to the spinal cord or nerve roots, and in addition, there is neither development of incapacitating deformity nor severe pain.”(3)
Neurological symptoms are likely to stem from the upper cervical spine (C0-C2)
Neurological symptoms are likely to stem from the upper cervical spine (C0-C2), as the atlantoaxial joint has the unique distinction of being the most mobile, least stable, and most narrow spinal canal region in the spine. Upper cervical spine instability has been implicated not just in a host of neurological symptoms but many ‘common’ chronic disorders that affect the brain including structural co-morbidities such as hypoplasia of dens (os odontoidium) and atlas (posterior arch) , Chiari malformation, and basilar invagination.
Conditions such as ponticulus posticous and Eagle’s syndrome, which stems from increased forces from a head forward facedown lifestyle; causing calcification of the stylohyoid and atlantooccipital ligaments respectively. Symptoms arise when these non-bendable ‘concrete-ligaments encroach on the neurovascular structures around them. For example, normally the vertebral artery travels in the vertebral artery grooves of the posterior atlas and has no impediments to movement; but once encased in the ‘bony’ arcuate foramen, it is more prone to kinking by upper cervical spine instability.
What are we seeing in this image?
Crowned dens syndrome gets its name from a crown-like appearance of the dens on imaging scans. Here we have an x-ray of a patient who has chondrocalcinosis (calcification) of the transverse ligament of the atlas. The patient presented with Crowned Dens Syndrome which is a medical condition associated with significant neck pain, elevated inflammatory markers, and stiffness. This can also affect the alar ligament.
The cervical spine ligaments
The cervical ligaments are strong bands of tissues that attach one cervical vertebra to another. The cervical ligaments are among the primary stabilizers of the neck. In our 2014 research lead by Danielle R. Steilen-Matias, MMS, PA-C, published in The Open Orthopaedics Journal (4), we demonstrated that when the neck ligaments are injured, they become elongated and loose, which causes excessive movement of the cervical vertebrae. In the upper cervical spine (C0-C2), this can cause a number of other symptoms including, but not limited to, nerve irritation, vertebrobasilar insufficiency with associated vertigo and dizziness, tinnitus, facial pain, arm pain, migraine headaches, and jugular vein compression.
Treating and stabilizing the cervical ligaments can alleviate these problems by preventing excessive abnormal vertebrae movement, the development or advancing of cervical osteoarthritis, and the myriad of problematic symptoms they cause including nerve, vein, and arterial compression.
The summary of this introduction to research can be seen as:
The damage, weakness, and dysfunction of the cervical spine ligaments can contribute to instability not solely through dysfunction of the passive subsystem (hold the bones of the neck in their proper alignment and preventing them from “wandering around” and compressing vital neurological and vascular structures, but also effects change in the ability of both the neural and active subsystems to compensate and adapt for stabilization of the spine. (It throws off your nervous system). Accordingly, ligament injury in the neurovascularly dense cervical spine has a unique role in leading to myriad symptoms.
The transverse and alar ligaments
The stability of the C0-C2 joints is due to the integrity of its ligamentous support. The ‘big two’ ligaments for the cranial cervical junction have long been thought to be the transverse and alar ligaments because of their attachment onto their anterior location to stabilize the dens, while the capsular ligaments which surround the C1-C2 facet joints located posteriorly have taken a backstage, but in reality, the capsular ligaments are more commonly injured, especially with the forward head facedown lifestyle, poor posture, or injury.
The transverse ligament positions the dens against the anterior (front) arch of the atlas. This allows the transverse ligament to provide correct and natural neck rotation and prevent anterior-posterior translation of C1 on C2 (sliding of the C1 on the C2), which would jeopardize the spinal cord.
The alar ligament, a secondary stabilizer of the dens, connects the cranium to C1 from the sides of the dens to the side borders of the foramen magnum. The alar ligaments function to prevent excessive axial rotation at the atlanto-occipital joint (to the right by the left alar and vice versa). Additional support to the occiput-atlantoaxial joints is provided by the apical ligaments.
In chronic wear and tear or injury, the atlantoaxial capsular ligaments are seen to fail before the alar and the transverse ligament being the strongest. Capsular ligament injury of C1-C2 causes lateral atlantoaxial instability whereas injury to the transverse and alar ligaments causes atlanto-dens instability. Injury to the atlantoaxial capsular ligaments causes a dramatic increase in lateral
bending and axial rotation motion; whereas transverse ligament disruption significantly increases the atlanto-dens interval. (The horizontal distance between the anterior arch of the atlas and the dens of the axis.)
What are we seeing in this image?
Rotational instability of the atlantoaxial joint. This person of whom this digital motion image was taken displays the inferior facet surface of the atlas (C1) rotates more than 50% from the atlas superior facet on movement. When the person rotates their head, upper cervical instability is drastic. An Atlas out of place can cause compression on the spinal cord, and the arteries, veins, and nerves that pass through the area.
What are we seeing in this image?
A tilted atlas. An Atlas out of place can cause compression on the spinal cord, and the arteries, veins, and nerves that pass through the area.
What are we seeing in this image? A visual description of how compression in the cervical spine can lead to problems of cervical spine neurology
Here we see that the carotid sheath and all its vital structures lays on top of the C1 Atlas. When the Atlas or C1 starts “wandering” out of place it takes the carotid sheath with it, stretching the arteries, veins, and the glossopharyngeal nerve and vagus nerve or compressing the arteries, veins, and glossopharyngeal nerve, and vagus nerve. When there is compression there can be symptomology. The person is now suffering from “neurologic-like” symptoms.
Symptomology and Conditions
The evidence that ligament laxity can cause neurologic-like symptoms is not well understood. For some of you reading this article, you may understand it. Your doctors may not. This is attested to by some of the emails we receive from people who are asking for an appointment for the simple reason: “I think I have craniocervical instability.” Or, “I have possible Craniocervical Instability.” This is a very complex problem to “think” you have and typically comes from people who have read a lot on their own, researched their problems, and have understood they may have a problem that is not being addressed. They may have come to the understanding that their doctors are “at a loss” for what is wrong with these people or are themselves grasping for answers to help these patients.
Other people have a more distinct understanding, they will write us about a medical history that sounds like this:
Cervicomedullary symptoms, dizziness, fainting or near fainting sensation, Autonomic dysfunction (may include digestive problems, fluctuations in blood pressure), inability to handle simple stress, severe headaches, insomnia, facial neuralgia, facial flushing, swallowing difficulty, etc.
Headache and Craniofacial Pain Syndromes
Headache and craniofacial pain syndrome may be brought about as a direct result of or be contributed to through cervical instability. For some people, orofacial pain can be eliminated with a deep cervical plexus block.
Cervical plexus blocks are challenging to deliver and can also be “hit or miss” they may work, they may not work and the understanding of why is not well understood. It is however understood that the blocks are symptomatic relief and not curative in nature in that they are not addressing the underlying cause of the cervical spine problems.
A February 2021 study in The Clinical Journal of Pain, (5) did provide a more optimistic look at pain relief in comparison to a placebo injection in the short term (2 weeks).
Understanding that “Myofascial pain is one of the most common causes of regional pain with no definitive treatment.” The researchers developed a randomized clinical trial to assess the efficacy of deep cervical plexus block versus placebo injection (sham block) for the treatment of myofascial neck and shoulder pain in terms of analgesic consumption (painkiller use post-injection) and pain during a follow-up period of 2 weeks after the block.
What they found was “Two weeks after the intervention (injection), the average pain duration was significantly lower in the block group. Pain intensity was significantly less in the block group such that 2.9% of patients in the block group had severe pain compared with 53.1% of patients in the placebo group. Two weeks after receiving the block, the mean opioid consumption calculated as tramadol equivalent was considerably lower in the block group than in the placebo group. Multivariate analysis showed that patients with a longer history of pain had a higher pain score after 2 weeks. The possibility of recovery is affected by pain duration as patients with a history of chronic pain were least affected by the block.”
- The longer you had chronic pain, the less effective the nerve block was.
- This was a study examining the first two weeks after the injection. It is not long-term.
An August 2018 study (6) previously reported on the challenges of accurately assessing block treatments:
What these researchers discussed was the varying nature of the structures of the neck. They wrote: “Currently, it is difficult to describe the true effects of each Cervical plexus block approach (superficial injection, intermediate injection, and deep injection), although most of the Cervical plexus block methods are now being performed accurately and safely under ultrasound guidance.” The deep cervical plexus block is recommended for headaches in many cases.
On our website are more detailed articles discussing treatment options for headache and craniofacial pain syndrome-related symptomology. These articles include:
- The secondary cough headache, cervical spine instability, and neck pain
- Cervicogenic headaches: Migraines, tension headaches, and cervical spine instability
- Can botulinum toxin injections for headaches make your symptoms worse?
- Occipital neuralgia and Suboccipital headache – C2 neuralgia treatments without nerve block or surgery
- Are Ehlers-Danlos Syndrome Headaches and Migraines Caused by Cervical Spine and Neck Instability?
- Digital Motion X-ray: Finding the missing cause of headaches, dizziness, and facial pain
- Cluster headache treatment – cervical ligament instability and the trigeminal and vagus nerves
- Suboccipital headache Getting results from cervical ligament repair and treatment of muscle spasms
Cervically Mediated Autonomic Symptoms (Barré-Liéou syndrome)
In June 2016, researchers writing in the journal Medical Hypotheses (7) noted: “Patients with cervical spondylosis often present with some atypical symptoms such as vertigo, headache, palpitation, nausea, abdominal discomfort, tinnitus, and blurred vision and hypomnesia. Although there are a few hypotheses about the etiology of those symptoms, none of them have provided evidence convincing enough to explain the clinical, pathological, and anatomic manifestation of those symptoms.
One of the more acceptable explanations is that those symptoms are the results of stimulation of the sympathetic nerves in the posterior longitudinal ligament. The clinical fact that dissection of the posterior longitudinal ligament significantly alleviates the severity of those symptoms seems like evidence for the validity of this hypothesis. However, recent clinical studies showed that laminoplasty, which has no effect on the posterior longitudinal ligament, can achieve a similar effect. In this paper, we hypothesize that stimulation of the dura mater and spinal cord might be the cause of atypical symptoms in patients with cervical spondylosis.”
What does all this mean? That neurologic-like symptomology of Barré-Liéou syndrome and other cervical spine-related disorders may be related to nerve messaging from ligaments.
What are we seeing in this image below? The idea that the ligament is a sensory organ. What does that mean? Let’s offer an explanation outline based on a paper in the Journal of electromyography and kinesiology. (8)
- Ligaments are major sensory organs, capable of monitoring relevant kinesthetic (movement) and proprioceptive data (limb movement and sense of place)
- Excitatory and inhibitory reflex arcs from sensory organs within the ligaments recruit/de-recruit the musculature to participate in maintaining joint stability as needed by the movement type performed.
- The synergy of the ligament and associated musculature allocates a prominent role for muscles in maintaining joint stability.
- The viscoelastic properties (the bad characteristic of being able to be stretched out) of ligaments decrease their effectiveness as joint restraint and stabilizers and as sensory organs and exposes the joint to injury.
- Let’s explain this point further when the ligament is damaged or stretched out, it loses its ability to control the neck muscle’s movements. Ligament instability brings with it, muscular instability).
In September 2015, our researchers including Ross Hauser, MD, and Danielle Steilen published our findings in the European Journal of Preventive Medicine on Cervical Instability as a Cause of Barré-Liéou Syndrome and Definitive Treatment with Prolotherapy: A Case Series. (9)
This paper is summarized here:
Barré-Lieou syndrome was discovered by and named after Jean Alexandre Barre, M.D., a French neurologist, and Yong-Choen Lieou, a Chinese physician. In 1925, Jean Alexandre Barré, and in 1928, Yong Choen Liéou, each independently described a syndrome presenting with headache, orbital pressure/pain, vertigo, and vasomotor disturbances and proposed that these symptoms were related to alterations in the posterior cervical sympathetic chain and vertebral artery blood flow in patients who had cervical spine arthritis or other arthritic disorders. (10,11)
Barré-Liéou and Cervicocranial syndrome are due to cervical vertebral instability, which affects the function of the nerve cell aggregations located in the neck just in front of the vertebrae. Vertebral instability or misalignment occurs because the ligaments that support the neck become weakened or injured. Vertebral instability, occurring after a neck ligament injury, affects the function of the cervical sympathetic ganglia (nerve bundle).
Treatment for Barré-Liéou syndrome is suboptimal and often involves long-term use of pain medications, chiropractic care, or surgical fusion.
Our website is filled with discussions about the cause of dizziness and vertigo. Two more prominent articles are:
- Persistent Postural Perceptual Dizziness and cervical spine instability
- Cervical Vertigo and Cervicogenic Dizziness | Can a pinched nerve in the neck cause vertigo?
Here, as our discussion surrounds neurologic-like symptoms – we will focus here on cervical instability and the Superior Cervical Sympathetic Ganglion.
Superior Cervical Sympathetic Ganglion.
For context, the superior cervical sympathetic ganglion is part of our flight-fight response. It is part of a messaging network that sends crucial instructions though out the body. The uniqueness of the superior cervical sympathetic ganglion is that it is the only ganglion (in simplest terms a nerve station that relays nerve messages) that innervates the head and neck.
Location, location, location. Compression, compression, compression.
What are we seeing in this image? The superior cervical sympathetic ganglion isolated so we can observe its proximity to the C2 vertebrae. Cervical instability that can lead to a “wandering” C1, C2, C3 vertebrae will impact the proper nervous system function of the vagus nerve and the superior cervical sympathetic ganglion.
What are we seeing in this image?
This is the superior cervical sympathetic ganglion in its native habitat. Surrounded by blood vessels (internal carotid artery and internal jugular vein) and nerve networks and near the C2 vertebrae. When the vertebrae wander out of position, it takes these veins, arteries, nerves, and nerve bundles with it, causing compression and stretching of these vital structures. In the context of this article, this compression and stretching can not only cause pain but disrupted nerve signals causing neurologic-like symptoms and conditions already outlined in this article.
The workings of the superior cervical sympathetic ganglion and problems of cervical spine instability.
In 1997 a team of researchers described the workings of the superior cervical sympathetic ganglion. (12) A keyword in the title of their paper was “communication.”
“Complex arborizations (the branching out at the end of nerve fibers) occur between the inferior ganglion of the vagus nerve and the superior cervical sympathetic ganglion. The superior cervical sympathetic ganglion sends branches to the internal and the external carotid arteries, the inferior vagal ganglion, the superior laryngeal nerve, and the cervical nerves, and provides superior cardiac and thyroid branches as well as the trunk that descends directly to the middle and inferior cervical sympathetic ganglia. There are communications between the vagus nerve (laryngeal branches) and the superior cervical sympathetic ganglion (SCSG). (Previous researchers) reported abnormalities of sympathetic function among the effects of injury to the superior laryngeal nerve during thyroid surgery. The interconnections between these various nerves are therefore of clinical importance.”
What does this mean? It may offer a clue to your neurologic-like symptoms.
Explanatory note: The inferior ganglion of the vagus nerve (nodose ganglion). In the nodose ganglion of the vagus nerve, the nerve cells and proteins, these essential components of a well-functioning autonomic nervous system, can be destroyed by vagal nerve compression.
The vagus, which is said to control everything
First some simple explanations to a complex problem.
In the illustration below, the many things the vagus nerve is responsible for.
- Psychologic-like functions in managing stress, anxiety, depression. Please see our article Dissociation, Anxiety and Depression – Uncontrolled emotion in cervical spine instability patients. Also please see our article Emotional stress: A neurologic and psychiatric-like condition caused by cervical spine instability.
- Digestive functions, swallowing, moving food through the digestive system, digestion of food.
- Cardiovascular-like functions to include regulation of blood press, heart rate, vascular tone
- Neurologic-like symptoms of:
- balance, dizziness, vertigo, and coordination issues. Please see our article Persistent Postural Perceptual Dizziness and cervical spine instability.
- Memory problems. Please see our article: Emotional stress: A neurologic and psychiatric-like condition caused by cervical spine instability.
- Chronic cough, throat clearing, and hiccups. Please refer to our article: Hiccups, Neck Pain, and Vagus and Phrenic Nerve Injury.
- Tactile hallucinations and Formication: Strange skin sensations including insects crawling on your skin.
- Brachioradial Pruritis – Neuropathic itch
Atlantoaxial subluxation or C2 malrotation may lead to compression of the superior cervical sympathetic ganglion
Atlantoaxial subluxation or C2 malrotation may lead to compression upon the superior cervical sympathetic ganglion which can explain symptoms such as vertigo and dizziness. Supporting this is the fact that the superior cervical sympathetic ganglion resides adjacent to the longus colli muscle, which has been reported to cause vertigo when tendonitis presents via stimulation of the cervical sympathetic ganglia. Additionally, atrophy of the longus colli and resultant decrease in the stabilization of the cervical spine was significantly associated with cervical vertigo in a retrospective analysis of cervical spine fusion patients divided into vertigo and non-vertigo groups.
A paper published in the medical journal Medicine (13) suggested: “The deep neck flexors include the longus colli and longus capitus muscles; these muscles play a vital role in cervical spine conditions and are frequently unnoticed as a source of locomotor system dysfunction. Dysfunction of the locomotor system may lead to the dizziness complaints, such as vertigo and disequilibrium. In most cases, neck pain, limitation of cervical spine movement due to pain, and swallowing complaints (odynophagia or dysphagia) comprise the classic triad of symptoms.”
Chronic Neck Pain and Blurred or Double Vision Problems – Is the answer in the neck ligaments and the Vagus Nerve?
Problems of blurred or double vision can be caused by many problems. Here we focus on the cause of neck instability causing pressure on the nerves, arteries, and veins that run through the cervical spine and into the skull. We are going to start with an introductory video by Ross Hauser, MD. Below the video is a summary of the video with explanatory notes to help further and explain some of the concepts that Dr. Hauser is putting forth in explaining vision problems as they relate to neck pain.
Summary learning points
- Dr. Hauser emphasizes that to understand the impact on symptoms of cervical neck instability causes, including ultimately vision problems, you have to understand that the nerves that travel the spine are so intertwined with each other and through the cervical vertebrae that any compression to the nerves will cause far-reaching problems.
- At 1:30 of the video: Dr. Hauser talks about C1-C2 instability and its impact on the Vagus Nerve (Cranial Nerve X)
- When the Vagus nerve is injured by compression caused by instability at C1-C2, this can cause vasospasms (narrowing of the arteries and reduction of blood flow). If these vasospasms impact the ophthalmic artery, the artery that supplies blood to the eye and eye area including the orbit – this can lead to some of the symptoms are patients describe to us such as darkening, black spots, or grayness in the vision of one eye.
At 2:00 Minutes of the video, Dr. Hauser refers to this slide: The details of what this slide says is below:
What is being described in the above image?
In this image, vision problems caused by cervical spine instability is connected to Diminished ocular blood flow, Exaggerated pupillary hippus dilating, Hampered accommodation or human ocular accommodation mechanism or accommodation reflex, Increased intraocular pressure or elevated intraocular pressure, Limited pupillary constriction, Optic nerve damage.
We have a more detailed discussion of vision problems in our article: Chronic Neck Pain and Blurred or Double Vision Problems.
Mast Cell Activation Syndrome
There is a connection between neck pain and instability and mast cell activation syndrome.
People will tell us that in their own research they came upon the idea that cranial cervical instability may be the cause of their prolonged illness including diagnosis of Chronic Fatigue Syndrome, myalgic encephalomyelitis, POTS, and Mast Cell Activation Syndrome. What we observe in our own patients and what we see in people that we talk to who are interested in becoming patients is that among their many symptoms is neck pain. However for some, their neck pain was seen as a manifestation of their illnesses, rarely was it seen as the cause of their illnesses.
So many of these people have taken it upon themselves to explore upper cervical instability and cervical spine instability as not a symptom, but rather a cause. These people then make appoints with Cervicocranial specialists who examine them and take imagining studies. In some of these images the patients learn that they degenerative disc disease in their cervical spine and a loss of the cervical curve contributing to kyphosis.
The confusion is some of these people’s diagnosis stems from not, what is the answer to help them? But what is the question we should be asking to him them. Namely, which came first the autonomic nervous dysfunction (the source of symptoms in the cervical spine) or the immune-mediated allergy? At minimum we know they are interconnected. A lot of antigen-antibody immune complexes and a host of histamine release is going to excite the autonomic nervous system throughout and likewise, autonomic nervous system dysfunction makes antigen-antibody reactions more likely. The patient has the symptoms, is it the neck? Is it the allergies?
When there is increase vagal tone in the enteric nervous system (which controls the skin reaction and gastrointestinal problems), this can cause an increase in motility (cell movement) as well as systemic mast cell activation, which can cause systemic itching, skin rashes, and even anaphylaxis.
Dysphonia and Voice Hoarseness
The neurologic-like symptoms and conditions of Cervical Spine Instability are often mixed, mingled, and concurrent. These challenges are seen throughout this article. The problem of voice, specifically hoarseness or Dysphonia, difficulties in speaking is seen as a problem of allergic type reaction in some people and a neurologic-type disorders in others. This is of course after the obvious problems of the larynx have been dismissed and doctors start searching for answers that are not in the throat.
Patients will tell stories that voice problems are just one of the many problems they have and that all these problems are seemingly unrelated. In fact their throat, voice and swallowing problems appeared one day “out of nowhere” and in some cases were accompanied by a new allergic reaction to foods they have always eaten without a problem. Sudden sensations of dizziness, fainting, skin rashes accompanied this new onset of symptoms.
While these people’s symptoms appeared to be an obvious allergic reaction, that was not the answer. A later diagnosis of mast cell activation syndrome was suspected. Further, in some, a diagnosis of upper cervical instability was suspected when underlying these symptoms was neck pain, inability to hold the head up, headaches, and twitches and tremors began to manifest themselves.
The vagus nerve, the symptoms, the voice
There are three motor branches of cranial nerve X (vagus nerve) that have bilateral upper motor neuron innervation (nerve signals that go up and down both sides of your neck that make various muscles move), and consist of
1) the pharyngeal branch, which supplies the muscles of the soft palate and pharynx;
2) the superior laryngeal nerve, which supplies the inferior pharyngeal constrictor (the muscles that also move food down your throat) and cricothyroid muscles of the larynx, which are responsible for pitch adjustments of the voice; and
3) the recurrent laryngeal branches, which innervate all of the other intrinsic muscles of the larynx.
Damage to the recurrent laryngeal nerve can temporary or permanently lead to hoarseness. In regard to voice, the sensory division of the vagus nerve receives information from the mucous membranes lining the larynx and vocal cords, and the stretch receptors in the muscle spindles of the larynx.
The larynx or voice box is involved in breathing, producing sound and protecting the trachea against food aspiration (going down the “wrong way.”) The larynx houses the vocal folds, and manipulates the pitch and volume of the voice, which is essential for phonation (the ability to make sounds). The larynx is located in the front of the neck at the level of C3-C6.
The muscles of the larynx are innervated by the vagus nerve.
When the vocal cords are abducted, air can enter and go into the lungs and we can breathe. When the vocal cords are adducted sounds are produced and we can speak. As mentioned, the vocal folds (cords) have to be closed also when swallowing so food does not ‘go down the wrong pipe’. The intrinsic laryngeal muscles are responsible for controlling sound production. Cricothyroid muscles lengthen and tense the vocal folds, as occurs with talking. Posterior cricoarytenoid muscles abduct and external rotate the arytenoid cartilages, resulting in abducted vocal folds. This is the position of breathing.
If both posterior cricoarytenoid muscles are not working from a bilateral recurrent laryngeal nerve injury, the person can have a very difficult time breathing. All muscles of the vocal cords are innervated by the recurrent branch of the vagus nerve except the cricothyroid muscles, which is innteravted by the external laryngeal branch of the superior laryngeal nerve, another branch of the vagus nerve.
A patient with a lesion in the laryngeal portion of the vagus nerve most likely will complain of a hoarse voice, difficulty in swallowing (dysphagia), and choking when drinking fluids. There can bea loss of the gag reflex or the uvula deviating away from the side of the lesion because there is a failure of the palate to elevate on that side because of loss of muscle strength of the levator palatini muscle.
The proper functioning of the larynx is critical for life itself. It is involved in swallowing, breathing, eating, coughing, vomiting and other vital functions. The sensory receptors in the larynx are innervated by the internal branch of the superior laryngeal nerve with cell bodies in the nodose ganglion. The nodose ganglion sits right by the transverse processes of the C1 vertebrae. There are many laryngeal neurologic reflexes that function during crises to keep the larynx open or closed. All of these reflexes are primarily dependent on the vagus nerve. Again the only muscle producing vocal fold (cord) opening in the larynx is the posterior cricoarytenoid. When it contracts it pulls the arytenoid backward and rocking the vocal process upward and laterally. It is constantly active with greater increases in tone during inspiration for vocal fold opening. This muscles is essential to life support. You need this muscle to work right otherwise air can not enter the lungs. People with cervical instability, can complain of shortness of breath, an inability to catch their breath or breathing difficulties.
What are we seeing in this illustration? The possible why of why you have symptoms.
- The vagus nerves supply “nerve communications” with the larynx.
- Proper, non-disruptive nerve input allows for good swallowing and speech. Disruptive nerve inputs impact swallowing and speech
- Further symptoms of poor vagus functioning, called vagopathy or vagal tone, affecting the larynx can be chronic cough, hoarseness, and as we will see below the contribution to chronic hiccup.
Whiplash associated disorders
At our center, we see many patients with chronic whiplash symptoms. They usually have taken a long medical journey bouncing from one clinician to another looking for answers to problems that seemingly evade all treatments. In this article, we will present our clinical findings and observations on how the treatment of cervical ligament damage may be the answer that has eluded them.
We have two extensive articles on the problems of whiplash:
- Treatment of Whiplash associated disorders
- Whiplash injury in the Ehlers-Danlos Syndrome patient
- When persistent post-concussion syndrome turns into a neurologic mystery
These articles are briefly summarized here:
In these articles we discuss and cite the research that many people with whiplash or post-concussion syndrome may have:
- Been treated with wrong or inappropriate treatments at the onset of whiplash. Unnecessary scans and images, the wrong specialist in many cases:
- Why physical therapy and exercise may not have helped them in alleviating their whiplash symptoms.
- Whiplash causes you more pain than imaging studies can verify – doctors can become skeptical of your pain.
- Functional somatic syndromes and somatization.
- What is somatization? It is very likely for some of you, that as your challenges continue, a suggestion to counseling or psychiatric evaluation was made. The understanding was that no one could figure out why you have more symptoms and more pain than you should. You must be in a situation of functional somatic syndromes and somatization. Somatization is a complex problem that can be simply described as the physical (pain manifestations) of psychological dysfunction. People who suffer from somatization have a deep suspicion of doctors.
- Whiplash-associated disorders – the first step in treatment? Have doctors believe Whiplash-associated disorders are real. The second step: have them believe something more can be done.
- How an apparently simple cervical spine injury can alter your thinking and sensation of pain.
- Swaying, posture control, balance, jaw pain TMD, head tremors, ringing in the ears (tinnitus) are whiplash-associated disorders and they are all connected.
- Swallowing difficulties.
- Some doctors do not believe that voice and swallowing difficulties can be attributed to whiplash-associated disorders.
In this video Danielle R. Steilen-Matias, MMS, PA-C, focuses on the injury to the cervical spine ligaments as the cause of degenerative disc disease in the cervical spine and the myriad of neurological and musculoskeletal conditions these injuries may cause.
A summary of the video is below:
Chronic post-whiplash symptoms: Treatment options
Ross Hauser, MD and Brian Hutcheson, DC discuss treatment options for chronic post-whiplash symptoms.
People with tinnitus can find benefit in many treatments. One aspect of tinnitus treatment is understanding the connection of tinnitus symptoms to cervical neck instability. Treatments that follow this connection will focus on strengthening the cervical spine neck ligaments. Repairing cervical spine neck ligaments can lead to an alleviation of tinnitus symptoms. Tinnitus can be a very complex condition to treat. Not all cases of tinnitus are caused by cervical neck ligament damage.
Tinnitus is a symptom of cervical spine instability
The idea that treating cervical spine instability as a method of treating tinnitus, is an idea that we, as well as many researchers and clinicians, have had for a long time. Yet recent research still has to present this idea as “novel” or new. Henk M Koning, MD, Ph.D., whose research is presented in this article published a paper in The International Tinnitus Journal (14) in November 2020 where he stated at the very onset “Treating cervical spine disorders can result in a reduction of tinnitus.”
Here are the summary learning points:
- The object of the study was to determine the benefit of (painkiller injection) therapy of the third and fourth cervical nerves in reducing tinnitus
- There were 37 tinnitus patients who were treated with injection into the third and fourth cervical nerves
- In a group of tinnitus patients, 19% of the patients reported less tinnitus after therapy of the third and fourth cervical nerves. Most of the patients had a moderate reduction of 25% to 50%.
- At 3.8 months, 50% of the successfully treated patients still had a positive effect. No adverse events of the procedure were observed.
Conclusions: “Treating cervical spine disorders can reduce tinnitus.”
We have many more extensive articles on the problems of Tinnitus: They can be found here:
- Tinnitus, cervical spine instability, and neck pain
- TMJ and Tinnitus: Should we explore the ligament chain from the cervical spine through the neck to the jaw to the ear?
In our article summary of our published case histories Dystonic storms in four patients with hypermobile Ehlers-Danlos syndrome describes a condition of Dystonia, that is a disorder in which your muscles spasm and contract involuntarily causing seizure like appearances. The “storm” is as it sounds, it can be the violent dangerous shaking and spasms. As with any disorder there can be degrees of severity.
What causes Dystonic storms? In many cases it has no known cause or origin. In our paper, we believe we have presented first-time evidence to the medical community of four cases of patients with hypermobile Ehlers-Danlos syndrome whose dystonic storms were reproduced by vascular occlusion (the mechanical blockage) of either the vertebral or carotid arteries in the neck. This condition caused intermittent cerebral ischemia (transient, temporary stroke), which was documented by cervical motion during upright transcranial doppler examination. (An ultrasound test used to measure cerebral blood flow velocity). Please see our articles Dystonic storms in four patients with hypermobile Ehlers-Danlos syndrome and our article Cervical dystonia and spasmodic torticollis treatment.
Emotional stress: Neurologic and psychiatric like conditions
In my article Emotional stress: A neurologic and psychiatric like condition caused by cervical spine instability, I wrote: “The neurology-like and psychiatric-like conditions caused by cervical spine instability: Vagal ganglion neuron destruction from emotional stress. If you have been battling chronic illness, you probably do not need a scientific article to convince you that your challenges come with an emotional price. However, it may be helpful to have some science that says your emotional stress is something more than “illness fatigue.”
“When we see patients, they rarely have one or two challenges facing them. In the case of emotional stress, this problem is usually listed at the end of a long line of symptoms and conditions. At the end of this list of neck pain, digestion problems, ear tubes, hearing problems, vision problems, and other neurologic-like, vascular-like symptoms and psychiatric-like conditions to name just a few, they tell us about their inability to stop taking opioids and antidepressants, and their inability to regulate or control their stress, anxiety, and emotions.”
In this article I also write: “To someone with strong vagus nerve function or vagal tone, stress can be managed. To someone with a low vagal tone, even the smallest stress can become emotionally and physically devastating.” Above I briefly outlined the role of the vagus nerve in neurologic-like disorders.”
What is being said in the research is the pathway to understanding why you get emotional for “no reason” or suffer from anxiety, depression, and hostility, can be a problem with vagal tone. This was demonstrated in a series of studies on affective, cognitive, and autonomic regulations showing that persons with higher levels of HRV (Heart Rate Variability) are more stress-tolerant and more adaptive in the face of diverse environmental challenges. Basically, when a person has a low HRV, they are hypervigilant in looking for what can go wrong (versus what can go right) and inefficient at properly allocating their attention and cognition to reach their goals. For more on this discussion please see my article Emotional stress: A neurologic and psychiatric like condition caused by cervical spine instability.
Treatment outlines – imaging studies and testing
Understanding the neurologic-like symptoms and conditions of cervical spine instability is challenging. It is more challenging when testing and imaging studies lead to inconclusive or non-defined results.
While imaging is not a treatment (it is a diagnostic) it is typically at the center point of treatment planning. Traditional radiographic testing including MRI’s, x-rays and CT scans are often done in the supine static position and can miss the diagnoses.
This may be borne out by your own experiences where you may suffer from dizziness or other symptoms and immediately lay down until the symptoms pass. In this supline position, you may have no symptoms. Yet when you stand up, your symptoms manifest.
Humans spend the larger part of each day in the upright position, the very position that causes most symptom’s yet most diagnostic tests are done with the patient in the laying down, resting
position, the very position (as just mentioned) that gives them relief. Scanning in the upright position can show the brain, brainstem and cervical spine under the effects of gravity but also its alterations in blood flow, venous drainage and cerebrospinal fluid flow can also be seen while the person is upright.
Many times symptomology occurs with a specific head/neck position such as flexion, so scanning the patient in the symptomatic position and motion will improve diagnostic accuracy.
Digital Motion X-ray helped reveal a series of missing diagnoses
Digital motion x-ray (DMX), also known as videofluoroscopy, offers real-time dynamic images (an x-ray movie). DMX allows unrestricted assessment of C0-C7 motion in multiple dimensions
including sagittal, rotational and frontal planes. DMX studies typically include moving the head and neck through protraction, retraction, flexion, extension, rotation and lateral flexion; while
observing in real-time, the motion of the cervical vertebrae from C0-C7. The DMX studies show the functional integrity of the ligaments in the cervical spine, specifically the anterior and
posterior longitudinal, supraspinous, interspinous, ligamentum flavum, facet capsular ligaments, transverse, and alar ligaments.
For many people, a digital motion x-ray can reveal a series of missing diagnoses and possibly end your chase for that elusive diagnosis that finally responds well to treatment. A digital motion x-ray is exactly what it is sounds like. It is a moving picture x-ray. In this video, Dr. Brian Hutcheson, DC shows how digital motion x-ray helped reveal a series of missing diagnoses in the case of a woman in her mid-30’s who happened to be a mother of three.
Digital Motion X-ray: Finding the missing diagnoses
Many patients with cervical spine instability have been chasing a diagnosis for years. At some point these people, probably you or your loved one, start to realize that their chase is nowhere near the end point because they continue to have worsening symptoms and continue to receive ineffective treatment with the addition of possibly unneeded medications that do not help. In our office, one of our diagnostic tools is a Digital Motion X-ray. We use tool because it can help reveal a missing diagnosis.
What are we seeing in this image? The patient’s lateral head tilt and a discovered problem
At 0:45 of this video, the motion of the patient’s neck reveals the head tilt problem.
In this image the tilting of the C1 in visualized on the digital motion x-ray. This tilted has created a visual space or a “hole,” that you can see through this patient’s cervical spine. That hole is not suppose to be there. In essence, the C1 vertebrae bone, which sits between the occiput or the base of the skull and the 2nd bone of the neck of vertebrae (C2) has moved out of place and is causing the patient’s symptoms of Head, neck, jaw and face pain.
For more information please see our article: Digital Motion X-ray: Finding the missing cause of headaches, dizziness, and facial pain.
At the Hauser Neck Center at Caring Medical Florida, we can utilize transcranial doppler (TCD) and extracranial doppler (ECD) ultrasound examination to assess proper blood flow during positional changes of the neck. Compromised blood supply traced to destruction of the cervical supporting structures and loss of cervical lordosis and cervical instability cause a wide array of symptoms. Dynamic transcranial doppler (TCD) and extracranial doppler (ECD) ultrasound provide documentation of any decreases in blood supply when the neck is in motion or in various positions.
Transcranial doppler (TCD) has been called the stethoscope for the brain. It can track moment to moment changes in blood flow to the brain, allowing us to assess the effect of interventions, such as changes in neck positioning, on brain blood flow. TCD can be used to monitor the brain blood flow for extended periods of time. Yes, we can be monitoring your brain blood flow while you walk around the office or move your neck.
Caring Medical Florida initiated a strenuous dynamic vagus nerve testing protocol to help patients assess the current status of their vagus tone and optimize recovery of it. The state of the nervous system is determined by its status at rest, its response to stress, and then recovery from that stress. The process of increasing one’s vagus nerve function is vital for life.
Comprehensive Cervical Ultrasound
Cervical ultrasound examination can reveal many findings that relate to cervical instability including differences in size and flow velocities of carotid and vertebral arteries and jugular veins, as well as evidence for dilated collateral vessels, lymphadenopathy, and measurements of pertinent nerve diameters including the vagus nerves.
Shots in Neck, Cervical Spine Curve Correction
At our center we offer non-surgical options to the treatment of the various disorders described above.
When instability is the primary structural issue, Prolotherapy injections to tighten the ligaments is started. Digital motion x-ray is then utilized to measure the amount of stabilization obtained.
Published research papers from our doctors at Caring Medical on Cervical Spine Instability and related symptoms
- Chronic Neck Pain: Making the Connection Between Capsular Ligament Laxity and Cervical Instability
- This paper was published in the European Journal of Preventive Medicine
- Steilen D, Hauser R, Woldin B, Sawyer S. Chronic neck pain: making the connection between capsular ligament laxity and cervical instability. The Open Orthopaedics Journal. 2014;8:326-345. [Google Scholar]
- The Biology of Prolotherapy and Its Application in Clinical Cervical Spine Instability and Chronic Neck Pain: A Retrospective Study
- This paper was published in the European Journal of Preventive Medicine
- Ross Hauser, MD, Steilen-Matias D, Gordin K. The biology of prolotherapy and its application in clinical cervical spine instability and chronic neck pain: a retrospective study. European Journal of Preventive Medicine. 2015;3(4):85-102. [Google Scholar]
- Non-Operative Treatment of Cervical Radiculopathy: A Three Part Article from the Approach of a Physiatrist, Chiropractor, and Physical Therapists
- This paper was published in the Journal of Prolotherapy
- Ross Hauser, MD, Batson G, Ferrigno C. Non-operative treatment of cervical radiculopathy: a three part article from the approach of a physiatrist, chiropractor, and physical therapists. Journal of Prolotherapy. 2009;1(4):217-231.
- Dextrose Prolotherapy for Unresolved Neck Pain
- This paper was published in Practical Pain Management
- Hauser R, Hauser M, Blakemore K. Dextrose prolotherapy for unresolved neck pain. Practical Pain Management. 2007;7(8):58-69.
- Cervical Instability as a Cause of Barré-Liéou Syndrome and Definitive Treatment with Prolotherapy: A Case Series
- This paper was published in the European Journal of Preventive Medicine
- Hauser R, Steilen-Matias D, Sprague IS. Cervical instability as a cause of Barré-Liéou syndrome and definitive treatment with prolotherapy: a case series. European Journal of Preventive Medicine. 2015;3(5):155-166. [Google Scholar]
The curvatures of the neck -What are we seeing in this image?
In our practice, we see problems of cervical spine instability caused by damaged or weakened cervical spine ligaments. With ligament weakness or laxity, the cervical vertebrae move out of place and progress into problems of chronic pain and neurological symptoms by distorting the natural curve of the spine. This illustration demonstrates the progression from Lordotic to Military to Kyphotic to “S” shape curve.
When initial testing reveals a person spine is stable but there is one or several misaligned cervical vertebrae (subluxations) that could account for the persons symptoms, dynamic orthoneurologic correct (DOC) is performed and the immediate response to treatment assessed. Sometimes the chiropractic adjustment is checked immediately via x-ray. When a loss of cervical curve is felt to be the primary anatomical issue causing the persons symptoms then cervical curve correction is started. The persons head and/or chest weights are checked via x-ray and the amount of time
wearing the weights is prescribed.
In this video, a demonstration of treatment is given
Prolotherapy is referred to as a regenerative injection technique (RIT) because it is based on the premise that the regenerative healing process can rebuild and repair damaged soft tissue structures. It is a simple injection treatment that addresses very complex issues.
This video jumps to 1:05 where the actual treatment begins.
This patient is having C1-C2 areas treated. Ross Hauser, MD, is giving the injections.
Summary and contact us. Can we help you? How do I know if I’m a good candidate?
We hope you found this article informative and it helped answer many of the questions you may have surrounding Craniocervical Instability, upper cervical spine instability, cervical spine instability, or simply problems related to neck pain… Just like you, we want to make sure you are a good fit for our clinic prior to accepting your case. While our mission is to help as many people with chronic pain as we can, sadly, we cannot accept all cases. We have a multi-step process so our team can really get to know you and your case to ensure that it sounds like you are a good fit for the unique testing and treatments that we offer here.
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This article was updated July 23, 2021