I know I normally keep the blogs lighthearted and fun, but this one will be more serious, not only because of accusations that can be made about chiropractic, but because of the misguided information some outlets choose to present chiropractic. I will look and comment on the outstanding research undertaken by chiropractors to discredit the notion that chiropractic can lead to a stroke.
First, let’s define a stroke. According to the Centers for Disease Control and Prevention (CDC), a stroke is a medical emergency that involves an interruption of blood flow to the brain. This causes brain cells to die and can lead to brain damage, long-term physical effects, and even death. Stroke is the 5th leading cause of death according to the CDC, following heart disease, cancer, chronic lower respiratory diseases, and unintentional injuries/accidents. There are two major types of stroke. First is an ischemic (or “dry”) stroke, which is caused by blockage that makes it difficult for blood to travel to the brain. Ischemic strokes account for 85% of all strokes. Second is a hemorrhagic (or “wet”) stroke, during which an artery ruptures and places pressure on the brain. Lesser-known strokes are vertebral artery dissections (VAD), which are most implicated in the chiropractic profession. VAD’s account for less than 2.5% of strokes and comprise 1/100,00 – 2.6/100,000 cases per year, if including carotid artery dissections as well (Tuchin, 2013).
Acting FAST are key to recognizing a Stroke.
My goal is to inform the public of the signs and symptoms of a VAD and assure you that VAD is not synonymous with chiropractic. VAD signs and symptoms include headache and neck pain, which can be diagnosed as musculoskeletal pain (Mattox et al., 2014; Tuchin, 2013). This means that patients can present to a chiropractic office with a VAD in progress. A case report described by Mattox and colleagues (2014) discusses a 45-year-old woman who presented with upper back/neck pain and stiffness. She also experienced headache and pain in the posterior portion of the right arm down to the elbow for 3 days. Before any adjustment took place, she was treated with therapeutic ultrasound and massage therapy. After modalities, she laid face up on the chiropractic table after which her headache worsened, visual disturbances and dizziness increased, and she experienced a loss of motor control in her right leg and difficulty speaking. The patient was sent to the ER after a 911 call was placed from the office. Not all cases are as clear as this one to indicate a stroke. Signs and symptoms to note are severe headache (particularly a headache different from any the patient has experienced prior), dizziness, and neck pain. Most importantly, this VAD was already in progress before any chiropractic adjustment was performed.
Studies have examined the integrity of the vertebral artery in compromising positions, specifically that of the chiropractic adjustment. Research found that there were no significant changes in blood flow or velocity in the vertebral arteries of healthy young male adults after various head positions and cervical spine manipulation (Quesnele et al., 2014). Time and time again, critics like to point out that VAD and chiropractic are linked, but research continues to find no significant relationship between the two (Herzong et al., 2012; Wuest et al., 2010). What about the internal carotid artery (ICA)? Some believe that stress-induced damage from cervical chiropractic adjustments can lead to internal carotid artery dissections. To test this theory, 8 cadaver specimens were tested. Researchers found that chiropractic adjustment of the neck did not cause strains to the ICA in excess of that experienced during normal everyday movements (Herzog et al., 2015).
We can comment on the research and knowledge that we do have. We know that chiropractors see a small percentage of the population; many more people per year have strokes than are seen by chiropractors. Additionally, Cassidy and colleagues (2008) examined over 800 individuals with VAD and concluded that “in the month before their stroke, only 16 (2.0%) of our cases had seen only a chiropractor, while 20 (2.4%) had seen both a chiropractor and PCP, and 417 (51.0%) had just seen only a PCP” (Cassidy et al., 2008, p. S181).
Naturally, this is a very important topic to me and research shows no causal relation between chiropractic adjustment and vertebral artery dissection. Of course, there is risk in absolutely everything – this is the nature of healthcare. Our job is to make decisions for each individual so that we can make life easier and more comfortable our patients. Chiropractic is a great tool that should not be written off because of critics’ misinformed opinions. These are the same critics who know of the prescription overdose epidemic cited by the CDC. They know about the “possible death” side effect attached to so many prescription drugs. Yet, they choose to report biased information about chiropractic. We know that VAD is possible when visiting a chiropractor, but we also know that the likelihood is 1 in 100,000. As mentioned above, the CDC reports that “accidents” result in more deaths (130,557/year) than stroke (128,978/year). Statistically, that means that a fatality from an everyday routine is more likely than suffering a stroke from a chiropractic adjustment. Research shows that those who experience a VAD are likely to consult with chiropractors orPCPs for the initial symptoms and develop the remaining symptoms afterwards (Cassidy et al., 2008). With proper examinations and awareness of signs and symptoms, a cerebrovascular accident can be diagnosed and serious consequences can be avoided.
Cassidy, J.D., Boyle, E., Cote, P., He, Y., Hogg-Johnson, S., Silver, F.L., & Bondy, S.J. (2008). Risk of vertebrobasilar stroke and chiropractic care. Spine, 33(4S); S176-S183.
Herzog, W., Tang, C., & Leonard, T. (2015). Internal carotid artery strains during high-speed, low-amplitude spinal manipulations of the neck. Journal of Manipulative and Physiological Therapeutics, 38(9); 664-671.
Herzog W, Leonard TR, Symons B, Tang C, Wuest S. (2012). Vertebral artery strains during high-speed, low amplitude cervical spinal manipulation. Journal of Electromyography and Kinesiology, 22; 740-746.
Mattox, R., Smith, L.W., & Kettner, N.W. (2014). Recognition of spontaneous vertebral artery dissection preempting spinal manipulative therapy: A patient presenting with neck pain and headache for chiropractic care. Journal of Chiropractic Medicine, 13; 90-95.
Murphy, D. (2012). Cervical manipulation and the myth of stroke. Medicine and Health Rhode Island, 95(6); 176-177.
Quesnele, J.J, Triano, J.J., Noseworthy, M.D., & Well, G.D. (2014). Changes in vertebral artery blood flow following various head positions and cervical spine manipulation. Journal of Manipulative and Physiological Theraputics, 37(1); 22-31.
Tuchin, P. (2013). Chiropractic and stroke: association or causation? International Journal of Clinical Practice, 67(9); 825-833.
Wuest S, Symons B, Leonard T, Herzog W.(2010).Preliminary report: biomechanics of vertebral artery segments C1-C6 during cervical spinal manipulation. Journal of Manipulative and Physiological Therapeutics, 33; 273-278.
http://www.cdc.gov/drugoverdos…
http://www.cdc.gov/stroke/