Cluster headache treatment – cervical ligament instability and the trigeminal and vagus nerves
Ross Hauser, MD, Caring Medical Florida
Cluster headache treatment – cervical ligament instability and the trigeminal and vagus nerves
If you are reading this article it is very likely that you have been on a long journey trying to find anything that will work for your cluster headaches. If you are like the people that have come to our clinics, your journey has included:
- frequent emergency room visits,
- coping with sleep disorders or sleep apnea because the cluster headaches wake you up in the middle of the night,
- a self-determined decision to stop taking medications that have not helped you,
- a self-determined decision to stop seeing doctors because some of the ones you have seen have made your situation worse.
- a consultation for nerve blocks, electrical nerve stimulation, and possible surgery.
Over the years we have seen many patients, who despite seeing many doctors, could not get help for their headaches. Why? Not all headache treatments work for all headaches. There are some patients that we have seen who had great success with a prescription for Verapamil. For these people, this success started to wane as they approached maximum dosage levels and a new prescription or treatment was necessary.
In this article, we will not examine which combination of medications, therapy, or neuromodulation techniques will work for you. If you are reading this article, it is unlikely you have had a long-term benefit from these treatments. What we will examine is something that may have been discussed with you briefly, that your headaches are coming from problems in your neck and possible compression of the vagus and trigeminal nerves.
Why so much confusion in getting treatment that can help?
A study from Harvard Medical School published March 2019 in The Medical Clinics of North America (1) suggested that most headache patients seeking medical treatments for their headaches symptoms will be diagnosed with a primary headache disorder, mostly migraine or tension-type headache. However, these patients may not be helped because there are other less commonly known primary headaches and secondary headaches that need to be considered in every patient presenting with a new-onset or change in headache symptoms and that headache treatments are varied, one medication will not work for all headaches and giving the wrong medication will make the situation worse.
And this may be your history. A visit form specialist to specialist and the elimination of what you do not have to try to understand what you do have. And here you are, still looking for treatment for what you most certainly have: terrible headache-related pain.
Understanding “lesser-known” headache types
In the research above, a suggestion is made to start looking for less obvious or “lesser-known,” headaches. How can this help?
What are these “lesser-known” headaches? Have they been explained to you?
- Lesser know headache group: Trigeminal autonomic cephalalgias, primarily cluster headache facial pain, primarily trigeminal neuralgia; and
- Lesser know headache group: Miscellaneous headache syndromes, such as hemicrania continua and new daily persistent headache.
These headache types are explained below.
The research also notes that facial pain and neuralgias constitute a large and distinct group of head pains with separate evaluation and treatment approaches. This can cause confusion in treatment.
- What the researchers point out is that the origins of your cluster headaches can be difficult to pinpoint. When causes are difficult to pinpoint, poor, inadequate or sometimes hurtful treatments can follow.
A brief understanding of cluster headaches source: Trigeminal autonomic cephalgia
In your medical journey, you may have had it explained to you that your headaches fall under a diagnosis of Trigeminal autonomic cephalgia. Cephalgia means cluster headaches. Simply, and as you are well aware, your headaches typically seem to be generated on one side of your face, centralized behind your eye. That eyelid may droop, you may have tearing or redness in that eye, and/or your nose may clog. These symptoms occur on the one side of your head and are caused by pressure on and travel the path along the trigeminal nerve.
The key points in the illustration are simple. As you know, your cluster headache can be a stabbing pain behind an eye or in the temple region.
- Now follow the path of the Trigeminal ganglion, the nerve bundle that branches. One branch is the ophthalmic nerve or the V1. This nerve provides impulses and innervation into the eye and upper lid/face region. The region of cluster headaches.
- Now follow the path of the maxillary nerve (V2) – it supplies nerve sensation from mouth to eye.
The illustration below points out that the “nuclei are situated within the CNS and the ganglia are outside of the CNS? What does this actually mean to you? This is a simple explanation:
- Your nervous system is comprised mainly of the central nervous system and the peripheral nervous system.
- The central nervous system or the CNS is your brain and spinal cord. When you have headache pain, the nerve impulses go to the spinal cord and brain so your body can make an assessment of what to do about this pain. As you well know, the brain and spinal cord do not have good answers most of the time.
- The peripheral nervous system or PNS are the nerves, which branch out from the spinal cord such as the Maxillary (V2) and Ophalmic (V1). What these nerves do is collect the information of pain in the face and behind the eye and send it to the spinal cord and brain so they can figure out what to do about it.
- Once the brain and spinal cord (the CNS) decide what to do, they send messages back to the peripheral nervous system (the Maxillary (V2) and Ophalmic (V1))
- Why it is important to note that the ganglia is outside of the Central Nervous System is because it can be subjected to nerve compression on its own. Cervical spine instability can cause compression on these nerves that cause pain, loss of sensation, or cluster headaches among a large myriad of symptoms. This nerve compression can also cause confusing and conflicting messages from the Maxillary (V2) and Ophalmic (V1) nerves. Your brain is not getting the right messages and it is responding to “bad information.” Your headaches are not only the result of this bad information but the cause as well.
The start of the chase for the root cause of the problem. The connection between the vagus nerve and the trigeminal nerve and trigeminal ganglion.
The vagus nerve, as illustrated below, travels through the cervical spine. It travels especially close to the C1, C2, C3 vertabrae. Cervical spine instability in these regions can cause herniation or pinching of the vagus nerve, which can lead to a disruption of normal nerve communication between the vagus nerve and the trigeminal nerve and trigeminal ganglion. This disruption or herniation of the nerve can cause among the many symptoms of cluster headaches.
An understanding of the interplay between the vagus nerve and the trigeminal nerve
In the medical journal Cephalalgia, (2) February 2019, researchers at Radboud University Medical Center in the Netherlands focused their attention on the vagus nerve for non-invasive stimulation in headache relief. They noted that the vagus nerve is thought to modulate the headache pain pathways in the brain.
The study showed that non-invasive stimulation of the vagus nerve in primary headache disorders is moderately effective, safe and well-tolerated.
The study also showed a deep and intricate entanglement between fibers of the vagus nerve and the trigeminal nerve.
Among their findings, the one that we want to illustrate is what the researchers suggest in their conclusion: “The moderate effectiveness of non-invasive stimulation of the vagus nerve in treating primary headache disorders can possibly be linked to the connections between the trigeminal and vagal systems.”
What we would like to point out here is that problems of cluster headaches as they relate to cervical neck instability, do not usually sit in isolation. It is usually a combination of problems that lead to difficult to treat or unresponsive cluster headaches. In this case the vagus and the trigeminal nerves.
Chasing the Trigeminal autonomic cephalalgia diagnosis
According to the National Institute of Neurological Disorders and Stroke: Trigeminal autonomic cephalalgias are primary headaches that include cluster headache, paroxysmal hemicrania, and short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing or cranial autonomic features.
Let’s briefly explain all of this.
- Paroxysmal hemicrania type headache
- Pain on one side of the face, around or behind the eye that can also radiate into the upper back and neck.
- A clue that this headache is being generated by a problem in the neck is that patients suggest that these headaches begin when they make a certain movement of their head.
- Another clue is that the patient is a woman. Women suffer from paroxysmal hemicrania more frequently than men.
Going back to the National Institute of Neurological Disorders and Stroke guidelines on treatment:
- Indomethacin (a non-steroidal anti-inflammatory medicine or NSAIDs) often provides complete relief from symptoms. Other less effective NSAIDs, calcium-channel blocking drugs (such as verapamil), and corticosteroids may be used to treat the disorder.
- Patients with both paroxysmal hemicrania and trigeminal neuralgia should receive treatment for each disorder.
More clues that your problem may be caused by cervical neck instability
It is likely that if you are researching cluster headaches, Indomethacin did not offer you complete relief. The recommendation that paroxysmal hemicrania and trigeminal neuralgia should be treated independently of each other is another clue that the problem may be in the neck. How? Because the medications needed for each disorder will not be effective for the other disorder. Therefore the medications are not treating a “common source of pain origin.” This may be the pressure on the nerves caused by cervical neck instability. This is something we see frequently in concurrent headache and head pain disorders where cervical neck instability is identified. We will discuss this further below.
Chasing another diagnosis: Is it Trigeminal neuralgia (nerve pain) or hemicrania continua (cluster headaches)?
Trigeminal neuralgia or nerve pain centers on what is happening to the trigeminal nerve which carries pain, feeling and sensation from the brain to the skin of the face. In the case of trigeminal neuralgia, most medical professionals cannot find the cause for why this pain started. This is borne out by the definition of trigeminal neuralgia.
- Trigeminal neuralgia means that there is nerve pain in the nerve distribution of the trigeminal nerve. It actually does not tell a person what is causing the condition. Please see our article: The evidence for Trigeminal Neuralgia non-surgical treatments.
Doctors are trying to treat a condition that they do not know what the cause is.
The missing or delayed diagnosis – why it took years to figure out what is causing your problems and why it may still be the wrong diagnosis
A June 2019 study in the Journal of Headache Pain (3) lead by King’s College London assessed headache disorders in patients coming into very specialized orofacial pain clinics after dental causes were ruled out. Of the one hundred and forty-two patients reviewed; there were 100 women (70%) and 42 men (30%).
- The most common diagnoses were
- possible trigeminal autonomic cephalalgia (44%),
- possible migraine ( 27%) and
- possible painful post-traumatic trigeminal neuropathy (12%).
- The most common trigeminal autonomic cephalalgia diagnosis was hemicrania continua (9%), which is higher than the reported prevalence in neurology and headache clinics.
The researchers also noted these findings on diagnosis prior to coming to the clinic
- Of the 142 patients, a previously suspected diagnosis was only reported in 17 patients, including six with trigeminal neuralgia, eight with, one with SUNCT (Short-lasting Unilateral Neuralgiform headache attacks with Conjunctival injection and Tearing), and two with painful trigeminal neuropathy
- However, only 7 had a correct previous diagnosis and, interestingly, trigeminal neuralgia was the most commonly misdiagnosed (5/6 patients).
- As a previous comorbidity, temporomandibular dysfunction was present in 10 (7%) patients. (Note: Please see our Caring Medical research article on the connection between TMJ/TMD and cervical neck pain to include headache.)
Delay to diagnosis
- Time to diagnosis for the whole study group was 5.6 years
- In patients with a confirmed trigeminal autonomic cephalalgia, the delay to diagnosis was 7 years.
- Time to diagnosis in patients with hemicrania continua, the most common diagnosis among trigeminal autonomic cephalalgias, was 8.7 years.
Cluster headache treatments
In this section we will look at various treatment options we will look at:
- Why didn’t medications help you? How did medications make your situation worse?
Cluster headache patients had MORE THAN 12 unique prescription drug claims.
Medication overuse headaches
In the medical journal Headache, (4) researchers looked at the medical history of 7589 patients suffering from cluster headaches. They found:
- 25% of cluster headache patients had MORE THAN 12 unique prescription drug claims.
Most commonly prescribed drug classes for cluster headache patients included:
- opiate agonists (41%), oxycodone and hydrocodone as examples
- corticosteroids (34%),
- 5HT-1 agonists (32%), intranasal zolmitriptan as example
- antidepressants (31%),
- NSAIDs (29%),
- anticonvulsants (28%),
- calcium antagonists (27%),
- and benzodiazepines (22%).
Only 30.4% of cluster headache patients received recognized cluster headache treatments without opioids during the 12-month post-index period. However, these patients were less likely to visit emergency departments or need hospitalizations (26.8%) as compared to cluster headache patients with no pharmacy claims for recognized cluster headache treatments or opioids (33.6%).
- Note: Notice the difference – not even 7% between those who took medications and needed to visit an emergency room or hospital and those who did not.
Overuse of medications especially indomethacin, eletriptan and tramadol
In August 2018, headache pain specialists in Italy published these findings in the journal Current Pain and Headache Reports (5):
Here are the points they learned from patients who had failed medication therapy:
- Overuse of medications especially indomethacin, eletriptan and tramadol
- Patients who underwent medication withdrawal treatments were more likely to be overusers of multiple drug classes and overuse higher amounts of symptom relief medications, particularly, indomethacin, eletriptan, and tramadol.
- Our comment: Notice in the above research that indomethacin often provides complete relief from symptoms. Not for these patients. These people took more than they should and were not benefitting.
- Patients who underwent medication withdrawal treatments were more likely to be overusers of multiple drug classes and overuse higher amounts of symptom relief medications, particularly, indomethacin, eletriptan, and tramadol.
- Frequent relapsers (people that were in medication withdrawal programs and relapsed) were more likely to be over users of opioids or ergotamine and caffeine derivates or of multiple classes, particularly acetylsalicylic acid and ergotamine/caffeine derivatives.
- The joint results of this review and clinical study do not seem to support the idea that Medication overuse headaches is drug-specific: rather, it points out that all drug classes may induce migraine chronification.
People who suffer most are the “worse patients” to get off of medications
- Those drugs which are at higher risk of overuse are among those preferred by the “worst” patients, i.e. those who needed one or more withdrawal treatments for Medication overuse headaches.
- Our comment: The withdrawal treatment has now become one of the major treatments the patient needs. The medications have made the patient’s situation much worse.
- These results reinforce the clinical impression that patients with chronic migraine and medication overuse headaches and particularly the most difficult to treat for their poor response to withdrawal treatments, are characterised by a particular drive towards the consumption of “whatever is likely to be perceived to provide some relief“, despite these drugs that are perceived as “more powerful”, are often indicated as second- or third-line medications.
Pain medications do help people. They do not help everyone. Some medications can make the situation worse.
In this section, we will briefly provide some research for you on the various medications you have been prescribed or are being recommended to.
Valproic Acid (Valporate)
An October 2016 study in the Journal of Clinical Neurology (6) found that people with a history of hyperlipidemia [including hypertriglyceridemia, hypercholesterolemia, and abnormally level of low-density lipoprotein (LDL) cholesterol] and hay fever and the complication of depression or other psychiatric disorder would not have a positive response to valproate and display a high risk of inconsistent responses to headache prevention treatment surrounded by Valproic Acid usage.
Flunarizine / Sibelium / Propanolol
A December 2018 study in the journal Pain (7) noted that flunarizine is considered a first-line preventative treatment for cluster migraines.
- Pooled research comparing numerous studies found flunarizine reduces the headache frequency by 0.4 attacks per 4 weeks compared with placebo. (Statistically a half an attack every 4 weeks).
- Analysis also revealed that the effectiveness of flunarizine prophylaxis (as a prevention from future headaches) is comparable with that of propranolol.
- The most frequent side-effects were sedation and weight increase.
Vitamins and Herbs? Do they help? Is it a Lack of Sunshine?
We are big proponents for the use of nutrition in healing the body but we have to be realistic. Vitamins and diet can help, they may help a lot, they may not help at all.
A July 2018 study in the International Journal of Clinical Practice (8) found that when compared with placebo, melatonin did not reduce the number of daily attacks. The good news was that when people took melatonin, it helped reduce daily painkiller analgesic consumption.
A January 2019 study in the journal Medicine, (9) was a little more optimistic if cautiously so. The researchers found that melatonin is very likely to benefit the prevention of migraines, BUT, it takes three months of consumption of melatonin to see benefits and how much benefit is found is debatable.
In The Journal of Headache and Pain, (10) researchers at Hallym University College of Medicine in Korea suggested that cluster headaches attacks may be related to sunlight and vitamin D metabolism. They wrote: “Vitamin D deficiency is common in patients with cluster headache, but the role of vitamin D deficiency is uncertain, except for its seasonal influence (a lack of sunshine).”
Vagus Nerve and trigeminal nerve stimulation with Non-invasive neuromodulation
Because of the limited effect of pharmacological medications on cluster headaches, researchers are exploring neuromodulation, or direct electrical stimulation on the vagus and trigeminal nerves
Neuromodulation may have been offered to you for your headache pain. This is the use of electric current to alter or modulate pain impulses. Non-invasive neuromodulation is where the electric stimulus remains outside of the body and are not implanted in the body.
A March 2019 study lead by German researchers and published in the Journal of Neurology, Neurosurgery, and Psychiatry (11) wrote:
- Non-invasive neuromodulation therapies for migraine and cluster headache are a practical and safe alternative to pharmacologics but research is very limited and simply not that good.
- Studies of all neuromodulation devices should strive to achieve the same high level of scientific rigor to allow for proper comparison across devices.
In other words, research is limited, but the treatment may help.
In December 2018 The FDA approved a twice-daily self-administered treatment that provides patients with 3 consecutive two-minute electrical stimulations through the skin of the neck that activates the vagus nerve to provide relief. In The Journal of Headache and Pain (12), December 2017 migraine and headache specialists in Germany found that patients receiving stimulation to the Vagus nerve and standard of care medications reduced cluster headache attack significantly more than with standard care alone in a four-week trial.
In June 2020, in the journal, Current Opinion in Neurology (13) researchers at King’s College London wrote: “Neuromodulation strategies aimed at anatomical structures involved in the pathophysiology of cluster headaches, such as the sphenopalatine ganglion (associated with the trigeminal nerve) and the vagus nerve, have proved effective in reducing the pain intensity and the number of attacks, and also to be safe and well-tolerated.”
While we do not use neuromodulation strategies, we do agree that addressing the pathophysiology of cluster headaches, such as the sphenopalatine ganglion (associated with the trigeminal nerve) and the vagus nerve is a path that needs to be explored.
In March 2019, neurosurgeons in Italy offered a summary of surgical techniques in the journal Neurological Sciences (14) and what they may be offered to patients for:
- “Craniofacial pain syndromes are comprised of multiple pathological entities resulting in pain referred to the scalp, face, or deeper cranial structures. In a small subset of patients affected by those syndromes, pharmacological and physical therapies fail in alleviating pain. In some of those refractory patients, surgical procedures aimed at relieving pain are indicated and have been adopted with variable results and safety profiles.”
- Craniofacial pain syndromes that most commonly fail to respond to pharmacological therapies and may respond to surgical procedures include trigeminal, glossopharyngeal, and occipital neuralgias as well as some primary headache syndromes such as cluster headache, and the trigeminal autonomic cephalalgia type headaches short unilateral neuralgiform headache with conjunctival injection and tearing/short unilateral neuralgiform headache with autonomic symptoms, and migraine.
- Surgical techniques include the implantation of deep brain or peripheral nerve electrodes with subsequent chronic stimulation, microvascular decompression of neurovascular conflicts, and percutaneous lesioning of neural structures.
Implantation of deep brain or peripheral nerve electrodes with subsequent chronic stimulation
Above we spoke about non-invasive neuromodulation. Here we will examine INVASIVE neuromodulation with the help of University of Minnesota researchers who published these observations in the journal Pain Research and Treatment.(15)
Here are the learning points:
- There is little evidence regarding the long-term effectiveness of Peripheral nerve stimulation therapy in managing chronic pain. Case reports and retrospective reviews do support that Peripheral nerve stimulation may be helpful in chronic pain from peripheral nerve injuries.
- However, in the context of the current opioid epidemic, when opioids kill nearly 42,000 people each year, it is important for healthcare providers to recognize potential non-drug therapies for treating chronic pain. Although randomized controlled studies are currently lacking, there is hope that neuromodulation devices may bring a new horizon for the treatment of chronic pain related to trauma, nerve injuries, and stroke.
Some people are helped by the surgical implant of stimulation devices. Some people are not.
Nerve compression surgery and non-surgical nerve compression options
Prolotherapy for headache
In 1993, Caring Medical opened its doors and among our first patients were people who suffered from chronic headaches. Sixteen years later we were able to document our experience in treating patients with headaches with Prolotherapy injections:
In 2009 we published research in the journal Practical Pain Management (16) that showed weak or loose neck ligaments and/or tendons may act as headache triggers because of the instability they created in the neck. Instability leads to hyper vertebrae motion and compression of nerves and arteries that may restrict blood flow into the brain.
- In our study, patients received Prolotherapy injections with a 15% dextrose, 0.2% lidocaine solution (as demonstrated in the video) No other therapies were used. The patients were asked to reduce or stop other pain medications and therapies they were using as much as the pain would allow.
Our findings strongly suggest that Prolotherapy injections can play a role in decreasing intensity level, frequency, duration, number of associated symptoms, and light sensitivity in patients with headache and migraine pain.
- One-hundred percent of patients reported they were at least somewhat better after receiving Prolotherapy, with
- 39% of these patients reported 100% improvement.
- 47% of patients stated the intensity of their pain was almost not noticeable after receiving treatment.
- A notable improvement in the duration of time they suffered from headache pain was also experienced after treatment.
- Seventy-three percent of patients reported a decreased sensitivity to light during a headache.
- Symptoms associated with tension and migraine headaches decreased in 80% of the patients in this study.
Throughout this article, we have made references to cervical neck instability causing pressure on the vagus and trigeminal nerves and the various treatment options offered to help remedy this situation. Some treatments work, some do not. We have illustrated these points above.
In our examination, we too are looking for compression.
In this video DMX displays Prolotherapy before and after treatments that resolved problems of a pinched nerve in the cervical spine
- In this video, we are using a Digital Motion X-Ray (DMX) to illustrate a complete resolution of a pinched nerve in the neck and accompanying symptoms.
- A before digital motion x-ray at 0:11
- At 0:18 the DMX reveals a completely closed neural foramina and a partially closed neural foramina
- At 0:34 DXM three months later after this patient had received two Prolotherapy treatments
- At 0:46 the previously completely closed neural foramina are now opening more, releasing pressure on the nerve
- At 1:00 another DMX two months later and after this patient had received four Prolotherapy treatments
- At 1:14 the previously completely closed neural foramina are now opening normally during motion
The head and neck, as all parts of the body, live in a complex relationship. Something in the neck can cause problems in the jaw, face, shoulders, fingers, etc. Problems in the jaw can cause problems in the neck. Any musculoskeletal problem can cause problems of headache. Back to the keyword “compression.” We are looking for problems in the neck that can be influencing problems of the head and jaw.
Common characteristics of cervical neck instability causing their headaches
In our patient interviews at our first meeting, we find that people with cluster type headaches:
- Constantly self-manipulates or cracks their neck.
- Constantly gets manipulation from chiropractors for neck pain.
- Suffers from constant muscle spasms in the neck.
- Had physical therapy with less than desired results.
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.
Cluster headaches are an extremely challenging problem. We have presented our case that Prolotherapy injections can be a viable option in stabilizing cervical neck instability and its possible cause of pressure on the vagus and trigeminal nerve.
If this article has helped you understand the problems of cluster headaches and you would like to explore Prolotherapy as a possible remedy, ask for help and information from our specialists
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