Spinal manipulative therapy does not cause strokes.
A stroke is “any acute clinical event, related to impairment of cerebral circulation, that lasts longer than 24 hours”(1). A common misconception about spinal manipulative therapy (SMT) is that it causes strokes, specifically vertebral artery dissections (VAD). There is lots of primary data (e.g., case reports, surveys, bio-mechanical studies, case-controlled studies) and even more secondary literature (e.g., review article, meta-analysis) written to determine the relationship between SMT and VAD; so how do we pick and choose the good ones? We are in luck: in 2010 Dr. Donald Murphy published a review article in the Journal of Chiropractic and Osteopathy reviewing every piece of relevant literature published and concluded, “The most plausible explanation for the association between [S]MT and VADS is that individuals who are experiencing a vertebral artery dissection seek care from a chiropractic physician or other manual practitioner for relief of the neck pain and headache that results from the dissection. Sometime after the visit the dissection proceeds along its natural course to produce arterial blockage, leading to stroke. This natural progression from dissection to stroke appears to occur independent of the application of [S]MT”(2).
Thus, SMT is independently correlated to VAD. But this patient self-referral phenomenon makes it the chiropractor’s job to differentially diagnose a patient with sudden onset unilateral neck pain and headache for a stroke. The proper questions to ask the patient are:
From here, the doctor should conduct a host of neurological examinations:
Based off the results of the neurologic exams, the doctor then has the proper amount of information to make a clinical decision. It basically comes down to whether the patient should be sent to the emergency room for a magnetic resonance angiography (MRA) or should be carefully treated in the doctor’s office.
Now, I know what you are thinking: Dr. Donald Murphy is a chiropractor, so he must be biased. So, in short, here is a similar conclusion from a famous study conducted by Haldeman et al. (a neurologist) published in the Journal of Neurology in 2002: “[VAS] should be considered a random and unpredictable complication of any neck movement including cervical manipulation. They can occur at any point in the course of treatment and with virtually any technique of manipulation”(3). Again, SMT is independently correlated to VAD.
These facts should ultimately bring you to your final question: Why should I care? Now that you understand how safe spinal manipulation is (you have an equal chance of stroking out by examining your s**t in the toilet bowel), the next step is to understand why SMT is clinically effective. We will explore the following question in the next post: How does Chiropractic Manipulation Work?
- Stedman’s Medical Dictionary for the Health Professions and Nursing. Philadelphia :Lippincott Williams & Wilkins, 2005. Print.
- Murphy, Donald R. “Current understanding of the relationship between cervical manipulation and stroke: what does it mean for the chiropractic profession?.” Chiropractic & osteopathy 18(2010):22-22. Web.
- Haldeman, Scott, Frank J Kohlbeck, and Marion McGregor. “Stroke, cerebral artery dissection, and cervical spine manipulation therapy.” Journal of neurology 249.8 (2002):1098-1104. Web.