Imagine that you’re a physician comparing two possible treatments for a patient: 'Treatment A' or 'Treatment B'. You review the medical literature and find that the most current evidence from multiple trials and systemic reviews shows that 'Treatment A' is effective [1-7]. In fact, studies that have directly compared 'Treatment A' with 'Treatment B' have found that 'Treatment A' was both more effective and less costly than 'Treatment B' [5-7]. You also find studies indicating that 'Treatment A' is much safer than 'Treatment B'. The risk of death from 'Treatment A' estimated at about 0.27 -10 per million [8-10] while the risk for death for 'Treatment B' is estimated at about 400-2800 per million [11-13].
Assuming there are no direct contraindications for either treatment, which of the following courses of action would you choose?
- Recommend 'Treatment A' to your patients; or,
- Recommend 'Treatment B' to your patients and write an article in Readers Digest and a blog post warning people that they should stay away from 'Treatment A' because it’s ineffective and risky
Let me introduce you to a physician who chose option 2, “PalMD”. PalMD recently tweeted a link to his blog post "Stay Away from Chiropractic Neck Manipulation". In this post he was responding to a chiropractor who accused PalMD of lying when he asserted in Readers Digest that, "Over the years, a number of my patients have had strokes after chiropractic neck manipulation." In this very real example, 'Treatment A' = chiropractic manipulation and 'Treatment B' = non-steroidal anti-inflammatory medications (NSAID).
While I can’t prove that PalMD is lying, I can certainly demonstrate that he’s at best uninformed. PalMD states that “While I don’t recommend chiropractic treatment to my patients, for those who use it I give them this information. I succinctly tell them that they should not let a chiropractor manipulate their neck. It’s just not worth it. I do the same for “mainstream” medical therapies whose risk benefit ratios are not favorable. It’s just good medicine.” Really? Is that so? I’m curious to know whether PalMD has ever prescribed NSAIDs for neck pain. If not, then what treatment is he prescribing?
Regarding effectiveness: PalMD states that “The best literature has failed to show a significant benefit of chiropractic neck manipulation vs. more conservative therapy for the treatment of neck pain.” This is patently false:
- A literature review of quality clinical trials (scoring above 11.5 on the Amsterdam-Maastricht Scale) found that “There is moderate- to high-quality evidence that subjects with chronic neck pain not due to whiplash and without arm pain and headaches show clinically important improvements from a course of spinal manipulation or mobilization at 6, 12, and up to 104 weeks posttreatment.”[1]
- A literature (Cochrane) review from 2004 found that mobilization and/or manipulation when used with exercise are beneficial for persistent mechanical neck disorders [3]
- A literature (Cochrane) review from 2010 found that cervical manipulation and mobilisation may provide immediate- or short-term improvement in pain and function [4]
- A clinical trial comparing manipulation with acupuncture and medication found that: “In patients with chronic spinal pain, manipulation, if not contraindicated, results in greater short-term improvement than acupuncture or medication.” The highest proportion of early (asymptomatic status) recovery was found for manipulation (27.3%), followed by acupuncture (9.4%) and medication (5%). [5]
- In a study evaluating the long-term benefits of medication (NSAIDs), acupuncture, and spinal manipulation researchers concluded that: “In patients with chronic spinal pain syndromes, spinal manipulation, if not contraindicated, may be the only treatment modality of the assessed regimens that provides broad and significant long-term benefit.” [6]
- A review published in the British Medical Journal concluded that, “Manual therapy (spinal mobilisation) is more effective and less costly for treating neck pain than physiotherapy or care by a general practitioner.” [7]
Regarding risk: PalMD states that “the evidence in the literature is quite clear: vertebral artery dissection (VAD), a type of stroke, is associated with chiropractic neck manipulation”. Again, this is incorrect. The current best evidence is the association between spinal manipulation and stroke is coincidental rather than causal. In fact, the most recent study concluded that “relying on case series or surveys of health care professionals may provide a biased view of who develops a VBA stroke” [14]. The largest population-based study to date was published in 2009 and included all vertebrobasilar artery (VBA) strokes in Ontario, Canada over a period of 9 years. The authors concluded that “We found no evidence of excess risk of VBA stroke associated chiropractic care compared to primary care.” [15]
Even if we use PalMD’s own statistic on strokes of “perhaps 1.5/100,000 manipulations”, PalMD concedes that chiropractic is extremely safe. However, the actual scientific literature puts the risk much lower at 0.027- 1 death per 100,000 (0.27-10 per million) [8-10] When you compare this with the estimated risk of death from NSAIDs (400-2800 per million) [11-13], chiropractic is much, much safer than prescribing NSAIDS. In fact, just getting your blood drawn is far more dangerous than spinal manipulation, causing roughly 40 deaths per million [16].
- A study from 2006 showed that the risk of stroke from any NSAID = 3815 per million, the risk of vascular death from any NSAID=2786 per million, and the risk of heart attack from any NSAID = 3644 per million [12].
- A 2002 review looked at severe gastrointestinal complications from NSAID use and found that risks ranged from 27,000 to 53,000 per million [13]
Let’s specifically take a look PalMD’s references. PalMD’s first reference [17] analyzed data from a countrywide survey of 21 neurological departments at university hospitals in Germany over a three year period of time. Over this 3 year period, 36 patients were identified who had a stroke within 2 days following cervical manipulation. Let’s put that in perspective shall we? The annual incidence rate of stroke in Germany is 1.34 per 1000 [18]. The population of Germany is 81,751,602. This means that over a 3 year period we would expect approximately 109,000 strokes per year; and well over 300,000 strokes over a 3 year period. It becomes very clear that stroke following chiropractic manipulation is exceedingly rare. And, if we look closer at the actual data from that study we see that even in the rare instance that manipulation was related to stroke, the majority of patient outcomes were generally mild:
- 6 of the 36 patients had no neurological deficit when they were admitted
- 10 of the remaining 30 patients were discharged within 2 days with zero clinical neurological deficits.
- In total, 21 of the 36 patients identified in this study had either zero neurological impairment, or “no significant disability”
- Of the remaining 15 patients who had some disability, 6 of those had only mild disability and were “able to look after own affairs without assistance”
This means that over a 3 year period in a country with a population of more than 81 million people, only 1 patient died following chiropractic manipulation and 8 patients were discharged with moderate to severe impairment.
Let’s look at another of PalMD’s references. In the Rothwell study, they looked at hospitalization records to identify VBA stroke patients in Ontario, Canada over a 5 year period [10]. Here is a direct quote from the authors: “VBA is a rare form of stroke. Despite the popularity of chiropractic therapy, the association with stroke is exceedingly difficult to study. Even in this population-based study the small number of events was problematic. Of the 582 VBA cases, only 9 had a cervical manipulation within 1 week of their VBA.” That’s 9 patients in 5 years! This is a very tiny number by any measure. The authors go on to state: “VBAs are rare events with potentially dire consequences. When they occur in otherwise healthy young adults, the natural tendency to seek explanation (recall or rumination bias) may exaggerate the apparent association with use of chiropractic services.”
Another of PalMD’s references [19] is more than a decade old and studied VBA stroke 74 patients in Canada over the course of a year. The data from this study showed that in 68% of these stroke cases the patient had not seen a chiropractor. In the majority of cases, the stroke occurred after such activities as: ”vigorous game of volleyball” or “mild exertion such as lifting a pet dog or during a bout of coughing.”
I certainly feel for patients who suffer a stroke for any reason and I take every precaution in my office to screen for risk factors. I also understand that there are some patients who have suffered a stroke following chiropractic manipulation. The fact remains that any medical intervention carries with it some risk, however small. I completely agree with PalMD that physicians should weigh the “risk benefit ratios” of treatments. I think it’s clear that the preponderance of evidence shows that 'Treatment A' far surpasses 'Treatment B' in this regard.
Unfortunately, physicians like PalMD continue to perpetuate an irrational fear of chiropractic while they repeatedly prescribe the poorer 'Treatment B'. These are often the same doctors bleating about “evidence-based medicine.” Personally, I’d like to believe that PalMD isn't a bad guy and that he's truly interested in the scientific evidence and in his patients’ health. Perhaps he was simply uninformed and didn’t actually read the references he provided. If that’s the case, I’m certain PalMD will begin referring appropriate patients for the far safer, more effective 'Treatment A' - chiropractic manipulation.
1. Vernon, H., K. Humphreys, and C. Hagino, Chronic Mechanical Neck Pain in Adults Treated by Manual Therapy: A Systematic Review of Change Scores in Randomized Clinical Trials. Journal of manipulative and physiological therapeutics, 2007. 30(3): p. 215-227.
2. Martinez-Segura, R., et al., Immediate Effects on Neck Pain and Active Range of Motion After a Single Cervical High-Velocity Low-Amplitude Manipulation in Subjects Presenting with Mechanical Neck Pain: A Randomized Controlled Trial. Journal of manipulative and physiological therapeutics, 2006. 29(7): p. 511-517.
3. Gross, A.R., et al., A Cochrane Review of Manipulation and Mobilization for Mechanical Neck Disorders. Spine, 2004. 29(14): p. 1541-1548 10.1097/01.BRS.0000131218.35875.ED.
4. Gross, A., et al., Manipulation or Mobilisation for Neck Pain. . Cochrane Database of Systematic Reviews, 2010. Reviews 2010(1).
5. Giles, L.G.F. and R. Muller, Chronic Spinal Pain: A Randomized Clinical Trial Comparing Medication, Acupuncture, and Spinal Manipulation. Spine, 2003. 28(14): p. 1490-1502.
6. Muller, R. and L.G.F. Giles, Long-Term Follow-up of a Randomized Clinical Trial Assessing the Efficacy of Medication, Acupuncture, and Spinal Manipulation for Chronic Mechanical Spinal Pain Syndromes. Journal of manipulative and physiological therapeutics, 2005. 28(1): p. 3-11.
7. Korthals-de Bos, I.B.C., et al., / Cost effectiveness of physiotherapy, manual therapy, and general practitioner care for neck pain: economic evaluation alongside a randomised controlled trial / Commentary: Bootstrapping simplifies appreciation of statistical inferences. BMJ, 2003. 326(7395): p. 911-914.
8. Hurwitz, E.L., et al., Manipulation and Mobilization of the Cervical Spine: A Systematic Review of the Literature. Spine, 1996. 21(15): p. 1746-1759.
9. Haldeman, S., et al., Arterial Dissections Following Cervical Manipulation: The Chiropractic Experience. Canadian Medical Association Journal 2001. 165(7): p. 905-906.
10. Rothwell, D.M., et al., Chiropractic Manipulation and Stroke : A Population-Based Case-Control Study. Stroke, 2001. 32(5): p. 1054-1060.
11. Dabbs, V. and W. Lauretti, A Risk Assessment of Cervical Manipulation vs. NSAIDs for the Treatment of Neck Pain. J Manipulative Physiol Ther, 1995. 18(8): p. 530-536.
12. Kearney, P.M., et al., Do selective cyclo-oxygenase-2 inhibitors and traditional non-steroidal anti-inflammatory drugs increase the risk of atherothrombosis? Meta-analysis of randomised trials. BMJ, 2006. 332(7553): p. 1302-1308.
13. Ofman, J.J., et al., A metaanalysis of severe upper gastrointestinal complications of nonsteroidal antiinflammatory drugs. The Journal of Rheumatology, 2002. 29(4): p. 804-812.
14. Choi, S., et al., A Population-Based Case-Series of Ontario Patients Who Develop a Vertebrobasilar Artery Stroke After Seeing a Chiropractor. Journal of manipulative and physiological therapeutics, 2011. 34(1): p. 15-22.
15. Cassidy, J.D., et al., Risk of Vertebrobasilar Stroke and Chiropractic Care: Results of a Population-Based Case-Control and Case-Crossover Study. Journal of manipulative and physiological therapeutics, 2009. 32(2): p. S201-S208.
16. Horowitz, S., Peripheral Nerve Injury and Causalgia Secondary to Routine Venipuncture. Neurology, 1994 (May). 44(5): p. 962-964.
17. Reuter, U., et al., Vertebral artery dissections after chiropractic neck manipulation in Germany over three years. Journal of Neurology, 2006. 253(6): p. 724-730.
18. Kolominsky-Rabas, P.L., et al., A Prospective Community-Based Study of Stroke in Germany—The Erlangen Stroke Project (ESPro) : Incidence and Case Fatality at 1, 3, and 12 Months. Stroke, 1998. 29(12): p. 2501-2506.
19. Norris, J.W., et al., Sudden neck movement and cervical artery dissection. Canadian Medical Association Journal, 2000. 163(1): p. 38-40.
