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Cervical Degeneration and Cervical Vertigo

Cervical vertigo is a controversial entity in the world of balance and vestibular disorders. It has generally been a diagnosis of exclusion when a patient is feeling dizzy but has no diagnosable pathology in the inner ear or brain.

The reality is that problems in the cervical spine are commonly linked to feelings of imbalance and disequilibrium. Cervical spine problems are rarely tied to the spinning rotational vertigo of someone having inner ear pathology. Most people with cervical “vertigo” really have which can include feelings of being really off balance, shaky, or a tilt like feeling of motion.

A 2018 study looked at how a degenerative problem in the neck can be associated with a diagnosis of cervical vertigo:

Mechanoreceptors in Diseased Cervical Intervertebral Disc and Vertigo

The study looked at patients with neck and arm pain related to cervical disc problems presenting for surgery. The patients were divided into patients with and without a complaint of vertigo. The patients with vertigo were examined to rule out other causes of vertigo like vestibular neuritis, benign positional vertigo, or stroke.

The research team examined the discs from patients with vertigo, without vertigo, and a control group of cadavers with no disc degeneration. The findings were really interesting.

In patients with vertigo, there are large increases in mechanical receptors in the degenerated discs compared to the patients without vertigo, and to the control group. These Ruffini Corpuscles help detect movement and position from your joints and muscles to help tell your brain what your joint is doing in space. Free nerve fibers are responsible for transmission of stimuli usually associated with pain. You can see the distribution below:

Patients with vertigo had significantly more Ruffini Corpuscles in their degenerated discs than the non-vertigo and control group. What does this mean for dizzy patients?
Patients with vertigo had significantly more Ruffini Corpuscles in their degenerated discs than the non-vertigo and control group. What does this mean for dizzy patients?
The data from the above chart in bar graph form showing increased receptors in the vertigo patients.

As expected, the patients with neck pain only, and neck pain with vertigo have a similar increases of free nerve fibers compared to controls. That’s probably why their neck is hurting.

However, a big reason why this study is interesting is because many people in the world of rehab and manual medicine would usually associate dizziness with a decrease in mechanical receptors in their spine, not an increase.

So what gives?

We don’t know exactly what this means, but it’s possible that increased density of these receptors may be transmitting excessive or erroneous information to the brain about the joint position.

The same group did a follow up study after they had performed disc surgeries on these patients. You can see the link to the study below:

Cervical Intervertebral Disc Degeneration Contributes to Dizziness: A Clinical and Immunohistochemical Study

During the study, they performed surgery on 50+ patients and 25 patients refused the surgery and received basic physical therapy and cervical collar recommendations. You can see the results below:

Comparison of patients with cervical dizziness and neck pain getting surgery vs routine physical therapy and neck bracing.

You can see that the patients who had the neck surgery showed clear and long lasting improvements in both neck pain and dizziness compared to the conservative group which implied that the degenerated disc was the probable source of bad sensory information to the brain.

So Is Surgery the Right Answer for Cervical Dizziness?

Maybe for some cases. If you have radiating arm pain with weakness tied to a badly herniated disc, then surgery might be able to help resolve both complaints, but there’s still a lot of research that needs to be done. Surgery is a BIG deal, and generally reserve that for really bad herniation cases with clear signs of neurological deficit like weakness, loss of reflexes, and atrophy of muscle.

The good news is there are a lot of ways to address cervical dizziness beyond routine physical therapy, and they have really great outcomes. One method is by improving the curve in the neck. A randomized trial of curve based rehab compared to routine physical therapy showed significant improvements in neck pain and dizziness at 1 year.

You can read some more about cervical curves and dizziness at this link:

Working on your curves: Long term outcomes from fixing military necks

A randomized clinical trial of cervical curve rehab on cervical dizziness

There’s also numerous cases of cervical dizziness that have no signs of degeneration in their spine. This is especially prevalent in patients with dizziness after whiplash and head injury in young athletes. These patients seem to do well when we focus on the upper neck where the injury is likely to affect the ligaments of the craniocervical junction.

Comparison of mulligan sustained natural apophyseal glides and maitland mobilizations for treatment of cervicogenic dizziness: a randomized controlled trial.

Long story short, degeneration of the cervical spine doesn’t have to be a sentencing for dizziness. It’s a risk factor, but it can be modified with the application of effective conservative interventions for the neck.

Working on Your Curves: Long Term Outcomes From Fixing Military Neck

I’ll admit that I’ve gone back and forth on the importance of cervical curves in my career. When I was in chiropractic school I was adamant about the importance of cervical curves and how the loss of a curve could affect the progression of spinal arthritis.

Then once I was in practice for a few years, I saw that most neck curves wouldn’t really change very much. Despite the fact that it didn’t change, I’d see really great changes and improvements of many of my patients, so I assumed that it is a nice feature, but probably not necessary to resolving a complaint. You can read some of my previous thoughts on cervical curves here:

I Have Military Neck: Now What?

So What Has Changed my Mind?

I still stand by my previous writings and say that having a proper neck curvature is a really good and positive thing, but you can still get really great results with most secondary conditions even if the neck curve doesn’t come back.

However, I have started to come around on the importance of having a proper neck curvature for the health of the human brain and nervous system. So what changed my mind?

Here are three pretty recent studies looking at the impact that cervical curve changes have on dizziness and cerebral blood flow.

Increase in cerebral blood flow indicated by increased cerebral arterial area and pixel intensity on brain magnetic resonance angiogram following correction of cervical lordosis

The first paper is a study that looked at consecutive patients getting imaging of the arteries going into the brain. Magnetic resonance angiography (MRA) measured the intensity of blood flow with the neck in patients with a straight or military neck pattern. The patients were then placed on a foam orthotic to produce a curve in the neck and a new MRA was taken with the neck in a curved position.

Before and after changes in blood flow to the brain using a device to improve cervical curve.

The patients’ MRA scans showed significant improvements in blood flow in the brain when they were lying on the orthotic with an improved cervical curve! The interesting thing is that it’s been known for years that a loss of cervical curve was associated with decreased blood flow in the brain, but there was no evidence showing that improving the curve would change blood flow. Now there is.

The effect of normalizing the sagittal cervical configuration on dizziness, neck pain, and cervicocephalic kinesthetic sensibility: a 1-year randomized controlled study.

While the previous paper is interesting, it’s limited by the small sample size and lack of controls. It was also a proof of concept study, and not one where an intervention was performed and tested to see if it made a difference long term. However, it may help explain why patients can get significant improvement in pain and dizziness.

This next paper features a randomized clinical trial of cervical curve correction along with cervical manual therapies compared to manual therapy alone for cervical dizziness.

The study looked at the results for patients with neck pain and dizziness for short term improvement at 10 weeks, and to see if they sustained improvement at a 1 year follow-up. The results are below.

Differences in patients with cervical dizziness at 10 weeks and 1 year. Changes after 10 weeks were similar to regular physical therapy, but the changes were hugely different at 1 year when there was an improved curve in the neck

The chart shows that the patients who were in the cervical curve correction group had significant improvements in head posture and curvature at 10 weeks, but the scores in pain and dizziness were pretty similar for both groups. Both groups got better, but they had similar improvements.

However, the changes at 1 year were impressive, and highlighted in red. While the control group had some regression into neck pain and dizziness, the cervical curve group maintained their symptomatic improvement much better. The mean improvements for both groups all crushed statistical significance, and the mean difference of the Dizziness Handicap Inventory (DHI) was by almost a whopping 30 points. That’s massive!

Does improvement towards a normal cervical sagittal configuration aid in the management of cervical myofascial pain syndrome: a 1- year randomized controlled trial.

A similar study was published on patients with persistent neck pain where physical manual therapy was compared to manual therapy and curve correction.

Just like the study involving dizziness, this paper on neck pain showed that both groups had similar improvements in scores on the Neck Pain Disability Index (NDI).

Changes in neck pain with manual thearpy and exercise alone vs manual therapy, exercise, and cervical curve restoration. Cervical curve patients were a little btter at 10 weeks, but were much better at 1 year follow up!

Again, like in the previous study, the 1-year follow-up is where things got interesting. The group that had treatment to improve their cervical curve had a much stronger ability to maintain their improvements in neck pain, while the control group started to return to their original pain scores. This was also largely statistically significant.

Long-Term Improvements Matter

So the big thing that changed my mind is that there is a growing body of work that supports the idea that creating structural changes in your cervical curve seem to help improve long term outcomes.

So while I still believe you can get significant improvement with or without a curve in your neck, your chances of maintaining your results over time seem to increase a LOT when you rehabilitate that curve.

Then you have the possible added benefit of improved blood flow to your brain, and that provides a potential bonus of better brain health.