Extreme rotation of the atlas on the axis (at the atlantoaxial joint) stretches the vertebral artery. In layman’s terms, 40% of a hanging.
I am off to Chicago for 5 days to wow the SMACC crowd with my ID/SBM acumen. I hope. Given that most of my multiple-personalities do not seem to be able to get any work done, I am forced to write a brief post this week, limited by the battery life on my MacBook Air. Whatever I get down on paper? pixels? RAM? before the battery dies as I fly over the Rockies will be the post. It is times like this I wish I had Gorskian typing skills.
SBM has discussed the many limitations of chiropractic: the low grades for entry into chiropractic school, the inadequate training, their reason d’être, subluxations and their adjustments being divorced from reality, the lack of efficacy of chiropractic for any process beyond low back pain (and even that is no better than safer interventions), the fondness of chiropractors for other useless pseudo-medicines, and their opposition to vaccines.
Hm. When I put it like that chiropractic does appear a little sketchy. But is chiropractic safe? It is a hands-on intervention, for a brief period of time applying the same force to the neck as about 40% of hanging from the neck until dead. So there is certainly the potential for chiropractic to cause harm. (more…)
The risk of suffering a stroke when undergoing aggressive chiropractic manipulation of the neck is not a new concern. We’ve discussed it several times on the pages of Science-Based Medicine over the years, most recently in November of 2014 when Steven Novella covered the death by chiropractor of 30-year-old Jeremy Youngblood, whose fatal brain injury occurred while seeking treatment for a sore neck. For a nice review of cervical manipulation in general, the evidence against its inappropriate use, and an assessment of the literature on this subject, check out prior posts by Dr. Hall and chiropractor Samuel Homola.
I believe that my take on the issue is in line with my fellow SBM authors. There is no role for high velocity, low amplitude (HVLA) thrust-type maneuvers that cause sudden and intense rotation of the neck in any patient, for any reason. It is not effective for neck pain, headache or any other complaint, and it is a proven risk factor for injury to the vertebral arteries and subsequent stroke. Some patients are at higher risk, such as the elderly or those with atherosclerosis or connective tissue disorders, but this type of injury can occur at any age and even in a perfectly healthy individual. (more…)
Chiropractors often deny that neck manipulation can be a primary cause of stroke by injuring vertebral arteries. But according to Jean-Yves Maigne, M.D., head of the Department of Physical Medicine at the Hôtel-Dieu Hospital in Paris, France:
It is now a well established fact that cervical thrust manipulation can harm the vertebral artery. This accident was formerly regarded as very rare, although severe, and related to atherosclerosis. Clinical tests were proposed to detect patients at risk. The problem is now better known. It is no longer attributed to atherosclerosis…but to a dissection of a vertebral artery, a clinical entity observed in younger patients (20-45 years). It remains very rare, but mild symptoms appear to be not so infrequent. Finally, the predicting tests seem to be deprived of any value.1
In 1997, the French Society of Orthopaedic and Osteopathic Manual Medicine (SOFMMOO), following presentations by anatomists, neurologists, radiologists, and practitioners in the field of French Manual Medicine, adopted the neck-manipulation proposals made by Dr. Maigne.1 “Acknowledging the fact that prevention is out of reach,” said Dr. Maigne, “the aim of these recommendations is to reduce the number of (not to say to suppress) rotational cervical thrust manipulations in a targeted population. This population consists mainly in females of less than 50 years old. Five recommendations were developed, in addition to classic contraindications of spinal manipulative therapy.”
The recommendations of the SOFMMOO, dealing with cervical manipulation in general and allowing the use of neck manipulation in special cases, are worth considering since they were reviewed by medical specialists in different disciplines and approved by licensed practitioners who use manual therapy, long before the stroke-neck-manipulation furor reached its peak in the United States.
Can neck manipulation cause strokes? Most MDs and many chiropractors agree that it can, but some chiropractors disagree. The subject has been covered on SBM before: here, here, here, here, here, here, here, here, and here. We keep returning to the subject not because it is a common problem (it isn’t), but because it is such a devastating one, and because the general public is still not aware of the risk.
A 2012 study published in the International Journal Of Clinical Practice “Assessing the risk of stroke from neck manipulation: a systematic review” concluded:
Conclusive evidence is lacking for a strong association between neck manipulation and stroke, but is also absent for no association.
Despite the uncertainty, they thought the association was strong enough to recommend informed consent be obtained and patients be warned that neck manipulation “may” increase the risk of a rare type of stroke.
A new study in the same journal, “Chiropractic and Stroke: Association or Causation?” applies Hill’s criteria of causation to the evidence and concludes that causality has not been determined. The author is Peter Tuchin, a senior lecturer in chiropractic at Macquarie University in Australia, and a known apologist for chiropractic. I agree with him that the existing evidence is inadequate to conclusively determine causality, but I think it supports a high probability of causality, and the alternate explanations he offers to exonerate chiropractors are questionable. And other factors should be considered, like the many “smoking gun” cases and whether there is any conclusive evidence of benefit to set against the possibility of risk. (more…)