The Craniocervical Junction and Headache Disorders

 

Headaches disorders are amongst the most common conditions that people seek treatment from a doctor. While most people will experience a headache of some form,  there are those who develop chronic and repetitive bouts with headaches of different types.

Unlike people who may struggle with an occasional stress headache or feel the effects from an alcohol induced hangover, people with these chronic headaches have a neurological disorder. These headache disorders can stem from:

  • Migraines
  • Cluster headache
  • Post-traumatic/Post-concussive headache
  • Chronic pain/Temporomandibular joint disorders
  • Tension headache
  • Chronic daily headache
  • And more

Each headache has unique characteristics that help to make an effective diagnosis for effective treatment. However, when we look at the reality of a daily patient interaction, we see that people with these headache disorders can have traits that overlap. (Remember this point because this is something I’ll come back to later)

That makes these headaches  extremely burdensome on the patient, but it can also be challenging for a doctor or therapist to find effective solutions. This is particularly challenging considering the rise of medication overuse headaches as a clinical entity in 2004.

Medication overuse headaches were once classified as rebound headaches because of the way headaches could come back with a vengeance after the pain-relieving effects of a medication wore off. It became re-classified in part due to the alarming number of patients showing a regression in their headache symptoms after prolonged and frequent use of medication. While the physiology of this disorder is widely unknown, it does show characteristics of physical dependency as seen with drug withdrawals.

As drug therapies become less effective for this subset of headache patients, there has become a growing need to identify non-pharmacologic strategies to help patients with headache disorders. For many of these patients, a possible solution might lie in the neck.

Headaches and the Cervical Spine

The concept of neck problems contributing to headache disorders isn’t new. Cervicogenic headache is a term coined in 1983 to describe patients suffering from simultaneous head and neck pain [1]. The term has grown to have diagnostic criteria that include:

  • Single sided head pain radiating from the top of the neck
  • Aggravation by specific neck positions
  • Reduced upper cervical motion or painful range of motion
  • Presence of muscular trigger points
  • Normal imaging
  • Unresponsiveness to pharmacologics

Cervicogenic headache does have a contentious history as a distinct clinical entity. Critics have argued that the soft nature of the diagnostic criteria. In the past, cervicogenic headaches seemed to be diagnosed by the effectiveness of cervical spine therapies in relieving the headache. You can see how this complicates the study of these headaches as a distinct clinical entity. In recent years, nerve blocks or ablations in targeted areas of the cervical spine have been used to determine if the cervical spine is the cause of the headache, but these also require more invasive procedures to make an assessment [2].

Headaches originating from the neck seems to have the biggest role in chronic headaches that begin after a concussion or whiplash. Headaches that emerge after these injuries are commonly classified as cervicogenic headache.The neurophysiologic effects of a concussion tend to disappear 7-14 days after the trauma but the ligament and muscle injuries from a head injury can persist leading to a default diagnosis of cervicogenic headace. The study of cervicogenic headache has revealed quite a bit about the physiology of how the neck can play a role in head pain, even those associated with migraine headache [3].

One problem with this idea is that fact that a traumatic injury can sometimes lead to patients who have never suffered a migraine before, can display migrainous symptoms after an injury [4]. This is also complicated by the fact that conservative cervical spine interventions like spinal manipulation and manual therapy appear to be effective in cervicogenic headache [5], but not in migraine [6] in clinical trials.

What do these headaches have in common? How are they different? Can we use their similarities to develop effective treatment strategies for headaches that are resistent to medications?

The Physiology of Headache Pain

There’s a common source for pain related to the head and neck. That source is a bundle of neurons located in the brain stem called the trigeminocervical nucleus (TCN). This nucleus is a hub for nociceptors in the brain. Nociceptors are receptors that transmit information about noxious stimuli to the brain, usually in the form of tissue injury.

While the feeling of pain is far more complex than the sheer amount of nociception your brain receives, for the sake of simplicity in this article, we will say that nociceptors are fibers that carry pain signals. Your TCN is a major player in head AND neck pain.

Head and neck pain pathway

This area in the brain stem is like the Grand Central Station for all of the pain sensing fibers in the head and neck. From the trigeminal nerve you have pain sensing fibers from the face, jaw, teeth, arteries, and meninges, while the neck has fibers from the joints, ligaments, muscles, and skin coming from C1, C2, and C3 nerve roots. All of these fibers converge onto TVN which has to decide if it’s worth going up to the big kahuna at the top of the brain called the cerebral cortex.

For neurovascular headaches like migraine and cluster headaches, it’s suspected that the pain carrying fibers from the arteries in the brain or the outer covering of the brain called the meninges getting irritated by pulsing arteries. These fibers are carried to the  TVN by the trigeminal nerve. For cervicogenic headaches, it’s suspected that the pain generators are coming from the muscles, nerves, or joints from the upper neck.

These overlapping structures allow for some of the referred pain patterns seen in migraine patients expressing neck pain, and also for cervicogenic dysfunction to lead to headaches. It also means that if 2 pieces of anatomy share a neurological pathway, then sometimes treating one area can lead to relief in another.

Interventions in the Cervical Spine and Headache Outcomes

So we know that the convergence of these neural fibers allows for some overlap of pain sensation regardless of the type of headache. What does the research say about treating headaches with cervical spine interventions?

The answer seems to match what you think it would be.

For cervicogenic headaches, recent studies seem to support the idea that addressing the neck with spinal manipulation can be helpful and even provide some relatively long term impact. A 2016 paper showed that upper cervical and thoracic manipulation helped cervicogenic headache patients at 3 months compared to exercise and mobilization [7]. A review paper of several studies on cervicogenic headache and manipulation seems well in favor of treating the neck compared to controls [8].

For migraines, the evidence isn’t so favorable for manual intervetions. There aren’t that many clinical trials to look at, and the ones that are available appear to show no effect [9]. From a pathophysiological standpoint it makes sense because they seem to be clinically distinct entities. However, the clinical experience of people like myself who practice in an upper cervical model of chiropractic have had a much different experience.

There is some evidence that suggests that cervical spine problems may be present as a sub-type of migraine patients [10]. There is also evidence that greater occipital nerve blocks [11] and non-invasive vagal nerve stimulation in the neck [12] can decrease the frequency of headache days and may effectively abort a migraine attack.

A 2016 study by Woodfield studied 11 patients with chronic migraines showing improvements in migraine frequency while receiving a vectored correction to the atlas vertebra [13]. The study also showed some significant effects in intracranial compliance in patients with cerebrovenous drainage abnormalities.

Case Study on NUCCA atlas procedure on venous drainage routes in a migraine patient.

While the concept of cerebrospinal venous abnormalities have been a controversial topic in multiple sclerosis, it may provide insight into some patients with chronic migraine. Multiple studies have documented venous drainage abnormalities in migraine patients and even mTBI, but the significance behind these observations are unknown [13] [14] [15].

Where To Go From Here?

There’s still a lot to learn about the anatomy and physiology of headache disorders. When you consider that migraine headaches are the most common neurological disease in the world.

Predicted research dollars compared to diseae burden

Lots of work needs to be done to understand what treatments will work for which patients, but there’s still some hope that treating the neck may be a key strategy to help people with chronic headache disorders.

 

 

 

How to Spot a Personal Injury Predator

Outline

  • The famously dirty personal injury industry
  • When profit leads to failed patient care
  • How to spot predatory practices

Personal injury (PI) is an famously dirty industry. When people think about PI, you usually think about ambulance chasing attorneys taking up local billboards, radio, and television commercials. In a state like Florida where just the act of a car crash can make you eligible for $2500 of personal injury protection at minimum, and many eligible for $10,000 of coverage from their insurance company, it has opened the door for many avenues of scams and unscrupulous activity.

Common fraud activity include people paid to stage accidents, forced referrals from tow truck companies, enticing victims with cash payments to go to certain clinics, and more.

Attorneys get a bad rap (some of them deserve it), but when it comes to your health after an accident it may be the doctor you choose that could be the biggest threat to your health and your money.

When Profit Leads to Failed Patient Care

While attorneys get most of the blame for a corrupt delivery system, unethical practices by healthcare providers have contributed to the problem.

There is an unspoken trust between medical providers and the public to always practice with the best interests of the patient in mind. While doctors will try their best to insulate themselves from getting too involved with the business side of medicine, the personal injury business has made it difficult to practice strictly based on clinical findings.

Health providers face pressure from patients and attorneys to help build a case for larger settlements. New doctors have large student debts to pay on top of trying to support their families. No one is trying to harm the patient, but it’s easy to see how money can muddy the waters of patient care.

So many patients are subjected to unnecessary imaging and procedures because of pressure from attorneys and patients to pad the medical bills and build a case for lawsuit. MRI’s are so widely prescribed for personal injury cases because the findings can show greater injury despite the fact that the correlation between imaging findings and pain are surprisingly weak.

Many patients with no pain have abnormal MRI findings, but these images can unreasonably scare and confuse patients about the real causes of their pain. Image Credit: Adam Meakins https://thesports.physio/

Many patients with no pain have abnormal MRI findings, but these images can unreasonably scare and confuse patients about the real causes of their pain.
Image Credit: Adam Meakins https://thesports.physio/

In some cases, offices and facilities have become places that exclusively see injured patients for the sake of billing thousands of dollars from insurance with little regard for appropriate management. Their only goal is to increase their billing as high as possible until the injury benefits are exhausted, and the patient is released from care regardless of whether they received the care they need.

This not only robs patients of benefits that may provide them with appropriate care from other providers, but it also causes patients take money out of the pocket of consumers as insurance premiums rise to pay for these unethical practices.

So what’s a person supposed to do? Here are some thoughts:

  1. Ask About the Expected Services and Fees Involved: When patients have the expectation that insurance will be paying for their services, they rarely ask about what services will be performed and the cost of these services.This might be okay if you have private insurance, but in capped payment systems like personal injury protection, doctors may be prescribing the same tests and procedures for all patients to get the bill to rise as fast as possible.Transparency in costs helps to control spending. If you knew that your x-rays were going to cost $500 of your own money, you’re a lot less likely to get it done unless you felt like it was necessary.If a doctor or staff is elusive about their fees and services saying things like “Oh don’t worry about that, your insurance will cover it.” Then press them on it. You will eventually get the explanation for their billing, and see if what they say and do actually matches up.

    Treat your insurance dollars like they are your own dollars, because when benefits start to run out and you’re not better, you may ultimately end up paying yourself.

  2. Check Your EOB’s and Your Statements: Insurance companies will send you an explanation of benefits to show patients what was billed for and what they paid for those services.In shady practices, you may see billing for services you’ve never received before. Patients who have never had an ultrasound machine touch them will see ultrasound in their billing. Patients who do a few arm circles may see a bill showing that 30 minutes of exercise is on the bill.This is a crime, and it’s called fraudulent billing, or just fraud for short. In the most extreme cases, you may see dates of service billed for days you know that you were never in the office.
  3. Are You Getting the Same 3 things Done over and over with no results?: Doctors who care about their clinical outcomes will design treatment plans based on your specific injury and how well you are responding to care.A sign that you are in a injury mill type practice is if you are being scheduled for the same treatments multiple times per week with no regard for how you are responding to care. This usually looks like getting electric stimulation and ultrasound placed on you by staff, a chiropractor manipulating your spine, and some vague recommendations for exercises. This is done 3-5x per week and the treatment doesn’t change despite the fact that you don’t feel any better, and sometimes continue to feel worse.Good practice is to triage your case based on the severity of your injuries. If you have a severe acute injury, you may need medical management from patches, meds, or injections so that you can feel functional as you go towards physical rehabilitation. Good practice also involves getting you to an appropriate specialist if you are not improving in a timely manner.

    When offices are not paying attention to whether the patient is getting better from their treatment, then it is a sign that they are trying to max out your benefits as quickly as possible.

  4. Are you being coerced to seeing certain doctors?:  Patients are always in control over what doctor they wish to see. If you have a comfort level with a certain doctor, then you always have the ability to find out if that doctor accepts personal injury claims.Some PIP schemes are set up to funnel patients into specific doctors’ offices for reasons that are not about helping the patient. At times people can be pushed into these offices by attorneys or patient runners saying they have to see a certain doctor for the purposes of the case. Some schemes will even go out and give patients financial compensation to go to specific offices which is outrageously illegal.This is a sign that there is an illegal kickback system involved that is built to just get maximum reimbursement from the PIP system.

Predatory PIP Practices Hurt Us All

So what’s the big deal if a practice is trying to max out your insurance money? After all, if you as a patient aren’t paying the bill then why should you care?

The truth is that these types of practices hurts us all. It hurts attorneys who are trying to build a business ethically in a dirty system that will spend more to get an advantage. It hurts doctors who treat patients for the best clinical outcome who may see insurance reimbursement go down to combat fraud.

Most of all, it hurts us all as people who want to trust attorneys, doctors, and the insurance company. As a doctor, you’ll usually expect me to trash insurance companies for cutting payments, but in terms of PIP many times it’s just a response to fraudulent or unethical billing practices. Insurance companies raise premiums on us all when fraud gets out of hand, and in some cases it makes it really hard to get insured at a reasonable rate after an accident lawsuit.

I have no sympathy for a multi-billion dollar industry, but I can certainly see why the system is built the way it is when I observe some of the scams that are run by people that are supposed to be the gate keepers of patient health.

This industry may be too far beyond repair and reform, but maybe it can get a little bit cleaner when patients are informed enough to call it out.

 

 

Ligament Injury: A Hidden Injury in Spinal Trauma

 

This guest post is brought to you by my friend and colleague Dr. Francisco Colon. Dr. Colon has been doing a lot medical-legal speaking on the role that ligament injury may play in pain after spinal trauma. He was kind enough to share a bit of his expertise in finding these soft tissue injuries that many physicians may be missing on a routine work up. You can find out more about Dr. Colon and his practice at his practice website Cordero Family Chiropractic

Ligament damage to the knee is something most of us have heard of in some regard. Either from personal experience or somebody we know. Detecting ligament damage to the knee is fairly easy to do. Any physician MD, DO, DC and most experienced nurses can easily test for ACL, PCL, and lateral ligament stability by applying basic orthopedic tests. Knee injuries are also well understood and addressed by health care professionals. In that regard, if you develop or acquire a ligament injury to the knee odds are any competent practitioner can easily test for, and send out for the right diagnostic images in order to get conclusive evidence. Unfortunately, this is not the case for ligament injury of the cervical and or lumbar spine.

Doctors have been playing around with x-ray technology since mid-to-late 1890’s. And we have a lot to show for 120 plus years of application and research. And since very early on physicians understood the role x-ray technology would play in detecting ligament damage to the spine. In fact, according to Yochum & Rowe’s Essentials of Skeletal Radiology: “In 1919 A. George called attention to the relevance of ascertaining alignment to detect post-traumatic cervical injuries”. When spinal anatomy is not in proper alignment with George’s line we call that a “break” or “step deformity”. In more scientific terms this is known as an anetrolisthesis or retrolisthesis depending on whether a vertebra slid forward or backwards in reference to the segment below it.

George's line

George’s lines drawn on a neutral lateral cervical x-ray. Looking for signs of a break or step.

As seen in the illustration George’s line can be seen from a side or lateral view of any portion of the spine and normally has an arch like shape. Since the moment it was described by A. George and in his book “A Method for More Accurate Study of Injuries to the Atlas and Axis” we have understood that there are 4 reasons and only 4 reasons for a break in this line. These are: dislocation, fracture, ligament laxity, and degenerative changes. These reasons have not changed since 1919. And the one we will focus on today is ligament laxity as a result of trauma.

Spotting Hidden Ligament Injuries

The most common reason for ligament damage to the knee is forceful trauma. It is the exact same for the ligaments of the spine. But unlike the knee, damage to the ligaments of the spine have  much more severe consequences and are the likely result of acceleration-deceleration injuries such as whiplash. More so, the American Medical Association indicates that “when routine x-rays are normal and severe trauma is absent ligament alteration is rare” (page 379 Guides to the Evaluation of Permanent Impairment 5th edition). In other words it takes a significant amount of force to overstretch and damage these ligaments. The AMA guides go on to say that when there is a break in adequate alignment and “severe trauma” is present flexion and extension x-rays are indicated.

George’s line is useful in identifying really gross ligament injuries, but remember that ligaments are supposed to hold things together in movement. If you sprain an ankle, the ankle doesn’t hurt nearly as much when it is neutral, but it hurts a whole lot when the ligament is stressed by movement. We can’t rely strictly on a neutral x-ray for ligament injuries, so we have to see what they look like when the neck moves.

Flexion and extension x-rays images taken of the side of the spine while the region (cervical, thoracic or lumbar) is in full flexion and also in extension (bending forward and bending back). From a practical standpoint this is the best way to stress the stabilizing ligaments of the spine. In the knee we can easily stress ligaments by manually applying pressure as it is a single superficial and large joint. Unfortunately the spine is not as easily tested and to avoid checking ligaments of the neck through the use of the “choke-hold method” a true professional will opt for x-rays.

 

Flexion stress x-ray may reveal injury to the posterior longitudinal ligaments

Flexion stress x-ray may reveal injury to the posterior longitudinal ligaments

 

 

extension x-ray

Extension stress x-ray may reveal injury to the anterior longutitudinal ligament.

It is also important to note that unlike the knee MRI and CT are will not show ligament damage as 99% of these images are taken in a neutral and recumbent position. This position will not stress the ligament structures enough to elicit evidence of Alteration of Motion Segment Integrity (AOMSI). In fact, standard trauma screening protocols miss discoligamentous injuries in an acute setting at a rate of 44% when CT is present and normal according to Alhilali and Fakhran. In a 2015 study titled Delayed or Missed Diagnosis of Cervical Instability after Traumatic Injury: Usefulness of Dynamic Flexion and Extension Radiographs, by: Gi Yeo, Jeon and Woo Kim discuss the following:

“In discoligamentous injury, 30%of patients with ligamentous disruption displayed a negative result on static radiographies and CT scan…Dynamic flexion extension radiographies are often recommended for patients complaining of neck pain or tenderness after an acceleration-deceleration mechanism injury, especially for patients presenting persistent symptoms in the absence of abnormal findings on standard 3-view radiograph including antero-posterior, lateral, and open mouth views…”

And they conclude:

“Dynamic flexion and extension radiographies are required to exclude the possibility of cervical instability in the patient with cervical trauma in initial or follow up studies. However the examination should be performed carefully to avoid neurologic deterioration.”

In short, the literature suggests that trauma protocols currently have many short comings and the knowledge practitioner should utilize dynamic flexion extension studies to document ligament damage. Concern for neurologic deteriorating has great validity as discussed in the British Journal of Radiology by Harison and Ostlere 2005 “Timely diagnosis of these injuries is imperative, as risk for neurologic sequelae is 10 times higher in patients with cervical injury missed on initial screening.”

The proposed mechanism for neurological deterioration that is expected with these injuries was evidenced and documented in a 2006 SPINE article by Nabili, Jiayong, Quaise Et.AL whereby it was documented that every millimeter of retrolisthesis allowed by ligament instability represents a 12% encroachment in the foramen. It is therefore evident that this hidden injury of the spine one that is very common place in trauma, one that is very easily overlooked and one with severe implications when undiagnosed.

Dr. Francisco Colón was born and raised in Puerto Rico. Dr. Colón decided to study chiropractic at Life University in Marietta, GA. In his last year of studies Dr. Francisco was part of a selected delegation of chiropractic students and Doctors that traveled to a hospital in China to educate and to provide chiropractic care. After graduating Life University in early 2010 Dr. Francisco moved to Miami where he practiced for 3 years with one of South Florida’s most successful chiropractic centers. Dr. Francisco has served a wide range of patients from the new born and healthy to the high performance athlete and the ill. He is committed to his new community of the Palm Beaches and will work hard to preserve the high quality of care that patients have received and have grown to expect from Cordero Family Chiropractic.

Looking at the Brain in Chronic Whiplash Injury

Injuries occurring after a motor vehicle collision can lead to chronic head and neck pain long after the damage of the injury is done repairing. These patients are generally classified as having chronic whiplash associated disorder (cWAD). A problem with cWAD is that we don’t really have a strong sense of why some people will get chronic pain after the injury while most will recover seemingly unphased.

Years of research studying biomechanical changes, ligament studies, and MRI changes in the neck have yet to show a diagnostic lesion that is predictive of a poor prognosis in whiplash patients. A number of studies have shown that psychosocial factors like work status, gender, and attorney retention appear to have a stronger correlation to chronic pain than any current medical diagnostics. This has allowed critics to say that chronic whiplash may be more psychosomatic than a true pathology. 1

How Whiplash Can Change the Brain

Conventional thought on whiplash has linked the pain of whiplash to a soft tissue injury in the cervical spine. When the neck undergoes rapid acceleration and deceleration, then the ligaments, muscles, and tendons of the cervical spine can be sprained and strained with varying levels of severity.

Instability of the cervical ligaments can lead to chronic pain in some trauma cases, but many patients who have chronic pain after an accident don’t have this level of injury. Many of these patients may even have close to normal imaging findings. Even in patients that have positive imaging findings, there’s not much difference between the imaging findings of those that will get better on their own and those that will have long lasting pain. 2

It’s easy to understand how injuries to muscular and ligamentous tissue can cause pain, but chronic whiplash injury is about more than just neck pain. Chronic whiplash often includes things like migraine headache, vertigo, and cognitive decline which are similar symptoms to mild traumatic brain injury. At least one study has shown that whiplash and concussion are indistinguishable based on symptoms alone. 3

When pain is poorly related to tissue injury, then it becomes more helpful to start thinking about pain as it relates to the brain itself. It’s easy to understand how the whipping of the head can tear and injure ligament and muscle tissue, but we have to dig a little deeper to see how whiplash can affect the brain.

Altered Cerebral Blood Flow

One of the best ways to see how a brain is changing is to monitor the way your brain uses blood. These studies are done using things like PET scans that help to identify areas of the brain that are gobbling up more glucose which tells us how active that part of the brain is at a given time.

Patients with chronic whiplash symptoms showed differences in blood flow in the brain in specific areas that play a role in how we perceive pain. These areas include the anterior cingulate cortex, insular cortex, medial prefrontal gyrus, and parahippocampus. 5

This is important because it tells us that the regions of the brain that are affected are NOT just the regions that perceive pain. Areas like the insular cortex and medial prefrontal gyrus are areas that aren’t directly responsible for feeling pain but are related to the limbic system and help us build context around pain.

If there are changes to the way these brain regions are wired, then we may also lose some of our ability to contextualize and inhibit our conscious perception of pain.

Image Source Unknown. If this is yours please contact us so we can credit you or remove.

Image Source Unknown. If this is yours please contact us so we can credit you or remove.

The belief amongst these authors is that there is a mismatch between the incoming pain stimulus and the level of activation in the pain processing centers of the brain.

Axon Injury

This mechanism is pretty similar to what can happen with a concussion. When the head and neck accelerate and decelerate during a collision, the force of the head and neck moving can be stopped by a seatbelt, but it won’t not stop the brain from moving inside the skull. As the brain shifts forward and back, it can create a shearing force in the brain and damage the neurons deep within the brain. The forces from an accident like this have been shown to be similar with the forces associated with a football concussion. 4

Whiplash and the Brain

While the force may not be enough to cause a concussion, the force profiles of a concussion and whiplash are likely high enough to cause some axon injury in the brain.

Although axonal injury doesn’t really correlate well to pain, it can impact our balance, postural control, vision, and other systems that help to keep us upright in a healthy way. Breakdown of these systems can help make sense of why whiplash patients can have vertigo, concentration problems, and headaches.

Central Hyperexcitability

Imagine if you sprained your ankle playing basketball one day, but weeks later after your ankle should have healed, you start to feel pain in other areas of your body that had nothing to do with the ankle sprain. This is the phenomenon of central sensitization which is caused by hyperexcitability of the neurons in your spinal cord. Although just one part of the body was injured, the effects of a central hyperexcitability is that you may feel increased pain throughout your body as a whole.

When we describe the injury of a whiplash as a sprain/strain, then it should have more in common with a sprained ankle in terms of tissue damage and repair. We expect sprains and strains to feel close to normal again in 4-6 weeks for minor sprains. However, the pain of a minor whiplash can last months. Why?

The way the body reacts to injury of a central structure like the spine can be a lot different than the way it responds to a distal structure like the ankle or wrist. When you injure your neck and back, your nervous system perceives movement as more catastrophic because there’s a chance that injury can occur to the spinal cord. Your CNS brings your pain neurons closer to their firing threshold so that they fire easier. By doing this, it is more likely to make movement more painful and immobilize you because your pain receptors will fire more easily. Immobilizing an area of injury is one of the main purposes for pain, because tissue repair is harder for the body if you have  a cut or broken bone moving around all the time.

That’s why when you go down with a neck or back injury, you can be really cautious or apprehensive about any type of movement. Your brain is playing defense against you out of fear that your next movement may be catastrophic to your survival. This may be your body’s wave of keeping you immobilized until the inflammatory and repair response is over.

This becomes very problematic when your central nervous system retains this hyperexcitability AFTER the injured tissues have healed. It leads to a condition where you are feeling pain everywhere, but there’s no blood test or imaging to point to why you are hurting.

This is probably the most important reason for chronic pain, not just in whiplash, but we see this in conditions like fibromyalgia or post-surgical pain syndromes. This isn’t a new idea either. Researchers have shown that central sensitization is a player in whiplash dating back to the early 2000’s. 5, 6

Changing How the Brain Perceives Pain

We know now that the brain and central nervous system can be re-wired in a way to cause chronic pain through a concept known as neural plasticity. We also know that neural plasticity can be used therapeutically to help make the brain more resilient and sometimes undo this maladaptive pain response.

Part of this means that we have to change our mindset about the nature of pain. Our patients yearn for a specific lesion with tissue damage to point to as the culprit for their pain. That way, if we get rid of the lesion, then the pain should follow suit. The obvious problem with this is that there may be no lesion at all. For some this will lead to despair and hopelessness, but for others it may lead to unnecessary procedures to cut or inject areas that are NOT the reason someone is hurting.

 

So if someone’s chronic pain is not coming from a pinched nerve, strained muscle, or injured ligament what is a doctor supposed to do for an ailing patient?

We have to engage patients in things that will change how the brain interacts with pain stimuli. Here’s a short list of useful strategies:

  1. Flip the script – Patients in pain are scared of movement because they think they are creating more injury. We can talk to our patients about this. If we have a level of confidence that pain is coming centrally, then we can teach patients not to fear their MRI or fear their movement. We can teach patients that moving their bodies may be painful right now, but they are NOT causing greater injury despite their pain. By giving patients a better sense of control over their bodies, their pain status can start dropping just by changing their mind.
  2. Lean into it – Patients consistently surprise themselves with how much pain they can tolerate as long as they know they aren’t harming themselves. Exercise and movement therapies can be powerful ways to affect central pain issues. Lots of people focus on doing exercise that help you avoid pain, but people with sensitization issues may benefit from leaning into the pain a bit. By gradually exposing the nervous system to movement with tolerable amounts of pain, you can train your body to tolerate that movement by desensitizing the fear response to that pain
  3. Adjust the Brain – most people and even many chiropractors attribute the benefits of chiropractic care to removing physical pressure on pinched nerves. This might be true in some cases, but it’s not the reason people with chronic pain syndromes get relief. A focus of chiropractic research in the past 10 years has studied how adjustments can change the way the brain processes sensory information.7, 8, 9When we combine these central changes from adjustments with movement therapies, we can make a big change in the way a person’s brain responds to movement.
  4. Biofeedback Tools– A unique way of addressing sensitization after whiplash is to use tools that provide real time feedback as a way to shift the brain’s attention on a painful area. Things like neurofeedback therapy with EEG, visual feedback with attached lasers, and wearable biofeedback devices allow the brain to shift it’s focus to another powerful stimuli. This provides a positive reinforcement to the patient to show that they can gain greater control over how pain shows up in their lives.

Closing Thoughts

The ability of our brains to change and adapt is an important piece of the rehabilitation process. While the above therapies are things I use in clinical practice on a day to day basis, these aren’t the only things that can help you recover. Our brain changes and adapts to ALL stimuli, and finding the right fit that works for you is the job of a good clinician.

  1. Dufton JA, Bruni SG, Kopec JA, Cassidy JD, Quon J. Delayed recovery in patients with whiplash-associated disorders. Injury. 2012 Jul;43(7):1141-7. doi: 10.1016/j.injury.2012.03.006. Epub 2012 Apr 2. PubMed PMID: 22475071.
  2. Curatolo M, Bogduk N, Ivancic PC, McLean SA, Siegmund GP, Winkelstein BA. The role of tissue damage in whiplash-associated disorders: discussion paper 1. Spine (Phila Pa 1976). 2011 Dec 1;36(25 Suppl):S309-15. doi: 10.1097/BRS.0b013e318238842a. Review. PubMed PMID: 22020601; PubMed Central PMCID: PMC3248632.
  3. Leddy JJ, Baker JG, Merchant A, Picano J, Gaile D, Matuszak J, Willer B. Brain or strain? Symptoms alone do not distinguish physiologic concussion from cervical/vestibular injury. Clin J Sport Med. 2015 May;25(3):237-42. doi: 10.1097/JSM.0000000000000128. PubMed PMID: 25051194.
  4. Elkin BS, Elliott JM, Siegmund GP. Whiplash Injury or Concussion? A Possible Biomechanical Explanation for Concussion Symptoms in Some Individuals Following a Rear-End Collision. J Orthop Sports Phys Ther. 2016 Oct;46(10):874-885. PubMed PMID: 27690834.
  5. Curatolo M, Petersen-Felix S, Arendt-Nielsen L, et al. Central hypersensitivity in chronic pain after whiplash injury. Clin J Pain. 2001 Dec; 17(4):306-315.
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  7. Bialosky JE, George SZ, Horn ME et al. Spinal manipulative therapy-specific changes in pain sensitivity in individuals with low back pain. J Pain. 2014 Feb; 15(2):136-148.
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  9. Haavik-Taylor H, Murphy B. Cervical spine manipulation alters sensorimotor integration: a somatosensory evoked potential study. Clin Neurophysiol. 2007 Feb; 118(2): 391-402.

Neck Strength and Concussion Risk

 

Neck muscles are historically one of the most unsexy muscles to train and develop in athletes. When we look at the main reasons that people take up training we find things like:

  1. Cosmetic (look better with less clothes)
  2. Enhanced performance in a specific sport
  3. Weight loss

The problem is that having a thick, strong neck is not seen as terribly sexy (especially for women) . A strong neck isn’t going to make professional scouts look at you closer on the football field, and certainly no one is asking you how much weight you can pull in neck extension.

In spite of these obstacles, there’s been a growing movement in sports science to pay more attention to the neck as a possible way to mitigate an athlete’s risk of concussion. Some circles are even hailing a strong neck as the only way to truly protect athletes from concussive head injuries. But what does the science say?

History of Neck Training

The buzz about strengthening the cervical spine came as a reaction to a 2014 study published in the Journal of Primary Prevention by Collins et al. [Source] The paper was on an observational study performed on over 6,000 high school athletes whose training staff assessed the strength of their necks and observed their risk of concussive injury over the course of a year.

The study found that people with smaller and weaker necks were at a higher risk of concussion during the school year. In fact, the defining sentence from the abstract shows why people were so excited about this study:

“For every one pound increase in neck strength, odds of concussion decreased by 5%” – Collins et al, 2014

The paper received a lot of buzz, and the idea of neck strengthening even became featured in a USA Today article featuring a colleague and renowned concussion expert Dr. Tad Seifert. [Source]

Truthfully, this is not a new concept to strength and conditioning coaches involved with boxing, mixed martial arts, and football. Neck exercises have been a staple in boxing for decades because stronger necks allowed fighters to take a harder punch. Just take a look at how Floyd Mayweather trains his neck.

A number of NFL teams became early adopters of weekly neck exercises to prepare their athletes for the inevitable high speed collisions that occur in football regularly. [Source]

How Does A Strong Neck Protect Your Brain?

A lot of the ideas about neck size and strength is related to the basic physics of acceleration.

Contrary to popular belief, a concussion is not simply a matter of taking a large blow to the head. Classically a concussion is seen through the lens of a coup/countercoup injury mechanism. An object strikes the skull, the skull hits the brain, and the brain hits the opposite side of the skull.

Classically brain injury is thought in terms of the brain colliding against the skull.

Classically brain injury is thought in terms of the brain colliding against the skull.

Much of the damage done to the brain and nervous system actually have a lot to do with acceleration and deceleration. This rapid acceleration and deceleration inside the head will cause a shearing force into the central structures of the brain including the midbrain, brain stem, and diencephalon.

The sudden deceleration in a concussion leads to tearing of the axons in the central portion of the brain.

The sudden deceleration in a concussion leads to tearing of the axons in the central portion of the brain.

That’s where a thicker and stronger neck may make a difference. Bigger and stronger neck muscles are capable of absorbing more force from an impact. That means that a strong and robust muscular system can take on that energy as opposed to letting the force go into the spinal ligaments and neural structures. If the amount of force of an impact is equal, then a bigger and stronger neck will be harder to accelerate which means decreased movement of the brain, and decreased shear into the central brain structures.

 

Do Neck Strengthening Programs Help?

As of now, we know that bigger and stronger necks are correlated with a reduction in concussion and this seems to make good sense. It helps to explain why girls have a higher rate of concussion than boys when playing equivalent sports like soccer [Source].

So here are the million dollar question:

Will neck strengthening reduce the incidence of concussion?

In other words; does someone who is naturally bigger and more muscular have a higher resistance to concussion, or can we train the neck to be more resilient?

In regards to concussion, we don’t really know the answer to that yet. There hasn’t been a study that compared groups of people who train their necks and how it impacts concussion rates….at least not yet.

We can make some educated guesses based on what’s been published in the literature about neck exercise and head stability, and neck exercise and general injuries.

The studies that looked at training programs and head acceleration don’t appear to be optimistic. Mansell et al looked at college soccer players using an 8 week neck training program found that training did not reduce head acceleration from a soccer ball header. Nor did it affect displacement, or EMG activity even though strength levels went up.[Source] Lisman et al found a similar result in trained college men during a football tackle. Although the men showed increased strength, there was no detectable difference in acceleration, displacement, or EMG activity. [Source – Lisman Paper]

Schmidt et al found that increasing stiffness of the neck does reduce rotational acceleration of the head, but parodoxically found that those with stronger and larger necks did not protect from higher impacts. [Source]

Most of the critiques of that study are that it tested stabilization in an unreliable way within a laboratory setting. Could results of players in a real setting dispute the acceleration data?

The data is pretty limited there, but a study of professional rugby players found that neck injuries did go down from one season to the next after the team participated in a 26 week neck training program. [Source] The rugby team focused mainly on isometric exercise which may mean more for an athlete because it is the neck’s ability to produce stiffness and stop motion that will help reduce the acceleration injury.

Thoughts on Neck Strengthening Programs

Thanks in part to the Collins study, there has been a greater effort to meet the demands of people wanting a way to prevent concussion by doing neck exercises. The list of contraptions that have hit the market that say they can prevent concussion is sometimes staggering.

Before you buy a fancy contraption for neck strength, we have to remember that neck muscles are like any other muscles in the body. If you repeatedly make them work against resistance, they will get stronger and be able to generate stiffness.

Some strength and conditioning coaches have advocated the idea that basic strength training alone will generate enough neck contraction without specific neck exercise, but this was disputed in a study by Conley in 1997. [Source] The study found that heavy compound lifts alone came up far short in terms of strength and hypertrophy than a program that included a neck specific exercise.

A review of published studies on different neck exercise programs showed that all kinds of neck exercises targeting the neck could produce measurable strength gains. These include isometric exercise, banded resistance, neck specific machine exercise, and even exercises against a coach’s manual resistance. [Source]

Ultimately, your neck is more likely to put on mass if you use a program that involves a neck harness with free weights or a machine with the ability to increase the resisted load. However, these studies have shown that subjects can make sizable strength gains within 8-12 weeks time by doing banded isometrics or using manual resistance even without hypertrophy.

In the end, you don’t need fancy equipment to get a strong neck. Just just need to do the work.

If you want a great guide for a wide range of neck exercises with video explanations, you probably won’t find a better resource then this article on Bret Contreras’ blog:

 My Take

As it stands today, we don’t truly know if you can truly reduce your odds of concussion through neck exercises, or if you just need to be born with the genes to have a big/thick neck. The good news is that anyone can do basic neck exercises on a regular basis for minimum investment and no real downside.

If you are an athlete that is in a high level combat or contact sport, it’s likely that you are already engaging in some form of neck training. For these athletes, it’s important to get your neck strong, but the truth is that there is probably a point of diminishing returns. Why? Because no amount of neck strength is likely to protect you from having a concussion after a hit like this:

 

No amount of neck strength is likely to stop this type of concussion.

No amount of neck strength is likely to stop this type of concussion.

 

Perhaps the biggest beneficiaries of a neck training program isn’t for professional athletes. It’s most likely to benefit our youth athletes and female athletes! The concussion rates in youth or female athletics may be a product of having a smaller or weaker neck. Many of the collisions in these sports are often a result of incidental contact, and are not as severe as those in tackle football, yet concussions happen more frequently.

Here are some other observations that aren’t proven yet by research, but I believe will play a role as we start to understand more.

  1. Proprioception may play just as important a role in susceptibility to concussion as strength. Exercises and treatments that focus on joint position sense proprioceptive stimulation seem to be helpful in rehabbing patients with concussion symptoms.Just like balance and proprioceptive exercises can help athletes mitigate ankle and knee injuries, I think these types of exercises may help the neck become a little more resilient to sprain/strain injuries.
  2. Isometric exercise may be more important than concentric exercise. Since we are talking about stopping acceleration of the head and neck, we want the neck to develop stiffness in response to an applied force.While taking a neck movement through full range with hundreds of pounds may be cool to some (unlikely), by making your neck resist moving against an applied force has a more realistic application than doing heavy neck curls.
  3. Don’t play a sport with a sore neck. If you are going to train your neck, do most of the training in the off season and do maintenance exercise programs during the season.Starting a program of neck exercises can and make your neck sore. Sore necks are not great at turning and avoiding danger. Sore necks are also more likely to instigate a headache/pain process for a short term. You don’t want that short term period to happen when you’re playing in a game for real.

 

 

 

Rectus Capitis Posterior Minor in Headache Disorders

Neck muscles have been a source of suffering for patients for a long time. In recent years, one neck muscle in particular is getting a lot of attention in the world of head injury.

Meet the rectus capitis posterior minor (RCPMi)

Image Credit: Duke Univeristy Learning labhttps://web.duke.edu/anatomy/Lab01/Lab2_new2014.html

Yep. It’s that tiny little muscle deep in the middle of your neck. It connects from the top bone in your neck called the atlas, and it connects into the head via connective tissue called the myodural bridge. But more on that later.

All in all, the the RCPMi is not much bigger than the end of your pinky finger, but it’s capable of wreaking havoc on people with neck problems including concussion.

Headaches, Trauma and the Rectus Capitis Posterior Minor

The RCPMi has been considered a muscle of importance in chiropractic literature for a long time. It’s only been a recent phenomenon where more mainstream medical science has started to look at its role in headaches and trauma. Two such studies examined the RCPMi in 2016.

The first study was published in the American Journal of Neuroradiology. They saw that patients with atrophy in the RCPMi had more severe concussion symptoms and a worse prognosis. You can check out the abstract here:

Effect of the suboccipital musculature on symptom severity and recovery after mild traumatic brain injury

The second study was published in the presigious headache journal, Cephalgia. The authors found that patients with chronic headache tended to have more hypertrophy in the RCPMi than controls. You can check out that abstract here:

Correlation between chronic headaches and the rectus capitis posterior minor muscle

In case you weren’t paying attention, you should probably find those 2 outcomes to be a little strange.

On one hand, having smaller RCPMi had worse outcomes with concussion symptoms. On the other hand, having larger RCPMi was more likely to be associated with chronic headaches.

Granted we are dealing with 2 different conditions, but one of the biggest problems with chronic concussive symptoms is chronic headache. It would seem like there should be some overlap. What gives?

How Can That Small Muscle Cause So Many Problems?

There’s a few unique things about these muscles.

  1. The RCPMi does not connect into bone like most muscles do. It connects into a piece of tissue called the myodural bridge. That means it has a direct link into the outer covering of the brain which is known to be very sensitive to pain.
  2. The RCPMi is too small to provide much in the way of meaningful movement of the head and neck. Inside the belly of this small muscle are abnormally large amounts of prorioceptors called muscle spindles. Proprioceptors help provide feedback to the brain about joint position and movement.
  3. Changes in the RCPMi can deform the myodural bridge which changes movement in cerebral spinal fluid. Abnormal movement of this fluid is associated with headache.

So as you can see, even though the RCPMi is small it carries a large baggage of neurology with it.

What’s Happening in Headaches and Concussions?

This is where things get a little interesting, because we don’t really know how this muscle is causing problems. More evidence is showing that there is a correlation between this muscle and headaches, but we don’t really know anything about causation yet.

With that being said, this is mostly just speculation on my part, so here it goes.

In my office we are always striving to create symmetry in the structural positioning of the head and neck.

When the head and neck shift, it creates asymmetrical force production in the suboccipital muscles. Image Credit: Daniel O. Clark uppercervicalillustrations.com

When there is an injury like a trauma or whiplash, you create injury in some of these small muscles of the neck. When these muscles are injured, the brain loses some critical feedback mechanisms that helped to maintain proper positioning of the head and neck.

The injury also creates asymmetrical tension on the myodural bridge. This abnormal tension on the dura stimulates the sensitive pain receptors in this tissue leading to head and neck pain. There have even been cases where cutting this muscle can relieve a patient of chronic headache.

That same tension on the dura may also be creating abnormal flow of cerebral spinal fluid which may lead to chronic effects of brain physiology.