Brady Workman is back this week with a post inspired by a patient we saw last week.
Dizziness and vertigo are common symptoms of patients within primary care clinics, with dizziness accounting for 2.5% and vertigo for around 1% of all patient visits. The majority of these symptoms are related to vestibular system dysfunction; however, other common causes for dizziness can include psychiatric/anxiety, cerebro-vascular, and/or brain/brainstem disorders. Seeing that the vestibular system is the most common culprit causing symptoms of dizziness and vertigo, much of the posts on this blog tend to focus on peripheral vestibular system dysfunction. However, there is a need to stay ever vigilant, as less common, benign or potentially life-threatening pathologies may present.
Just this past week we saw a patient who reported symptoms of imbalance, which were exacerbated by walking in darkness or on uneven surfaces, and blurred vision, especially when turning their head to the right. This patient denied any symptoms of vertigo or lightheadedness. With this patient’s symptomology, I wasn’t particularly suspicious of a peripheral vestibular disorder, but we completed our typical vestibular assessment battery including: rotational chair, positional/positioning tests, oculomotor, video head impulse and caloric irrigations. All of these measures were found to be within normal limits, showing no evidence of vestibular system dysfunction, with the exception of a persistent 5 degree/second downbeat nystagmus in Dix Hallpike head left. Due to this patient’s reports of blurred vision with turning their head to the right, we performed a vertebral artery-screening test while utilizing video goggles. It was noted that on having this patient turn their head to the right while sitting upright, a persistent 10-11 degree/second down beating nystagmus was observed with no evident nystagmus in the head turned left position. This would be considered a failed vertebral artery-screening test. This was a surprising finding, especially given that the patient was in their mid 30s with no significant cerebro-vascular risk factors, did not report any neck pain, nor had they had recent head or neck trauma. One can only presume that this patient’s symptom of blurred vision with head turns to the right was due to the significant down beating nystagmus. It is possible that the symptom of imbalance on unfamiliar surfaces could also be related.
In this instance not all routes have yet to be explored, so at the time of writing this one cannot make a diagnosis of cervical vertigo, but the patient’s symptomology, failed vertebral artery screening measure and lack of other significant findings makes this a possibility worth exploring. This surprising case led me to further investigate cervical vertigo. Cervical vertigo is a diagnosis of exclusion and is somewhat controversial with disagreement on the exact causative etiology, prevalence and typical symptomology. Cervical vertigo simply refers to symptoms of dizziness or vertigo that are provoked by the posture of the neck. That is to say dizziness symptoms provoked by twisting of the neck from midline. Symptoms of cervical vertigo are attributed to abnormalities of the cervical spine or the lower brainstem vascular supply and are provoked due to a lack of blood supply to the brain. This decreased blood supply to the brain can be caused by compression or dissection of the supplying vertebral arteries. One would expect symptoms of cervical vertigo to be similar to other etiologies causing decreased blood flow to the brainstem, such as: vertigo, lightheadedness, nausea, and slurring of speech. Symptoms of imbalance and gait instability are also possible with cervical vertigo due to changes in the proprioceptive input from the neck muscles, which assist in postural control. It is also important to note that positioning/positional nystagmus may be present in patients with cervical vertigo; however, it is the torsion of the neck, not gravity, causing the nystagmus.
Cervical vertigo is thought to be most common following head or whiplash neck injury. Other potential provoking factors could include degeneration of the cervical spine, arthritis, arteriosclerosis and neck surgery.
To screen patients in the clinic for cervical causes of their symptoms, clinicians can implement a vertebral artery-screening test. To perform this measure, clinicians should have the patient sit upright and turn their head as far at they can to one side and hold this position for 30 seconds, best done before performing the Dix-Hallpike. During this time period, the patient’s eyes should be observed for nystagmus. Also, clinicians should listen for subjective reports of blurred or double vision, lightheadedness, or nausea. The patient’s speech should be monitored, as slurred speech may be possible. This should be performed with the patient’s head to the left and to the right, carefully observing in both directions.
As previously stated, cervical vertigo is a controversial diagnosis and one that is achieved by excluding other likely causes of symptoms. Treatments can include physical therapy focused on neck mobility, medical, and/or surgical management. A more in depth discussion of cervical vertigo causative etiologies, diagnosis, and treatment can be found here.
Photo courtesy of WWS Physical Therapy and Vestibular Rehabilitation