Safety of Chiropractic Care - Neck Manipulation

The efficacy of spinal manipulative therapy (SMT) has been a topic of research for more than 20 years now and has subsequently been recognized as such in at least four countries which has led to increased integration of chiropractors into mainstream healthcare.[1] This greater predominance has led to questions regarding the possibility of complications due to SMT, especially with respect to manipulation of the cervical spine (neck).

This was never more prevalent than after two tragic events following chiropractic care in Canada in the 1990s which spurred rabid media attention and an adamant stance by the neurology community to avoid cervical manipulation as a treatment for neck pain.[2] These events have no less been the provocative factor for the publication of several case reports in which chiropractors have been incorrectly identified as the practitioner responsible for injuries related to SMT.[3] This fact is inescapable when reviewing two articles published in the Journal of Neurology where the authors cite 46 cases involving stroke and/or vertebral artery dissection due to “chiropractic manipulation”. Truth be told only FOUR (4) of the cases involved chiropractors the remaining 42 cases (91%) of injury due to cervical manipulation were induced by 25 -orthopedists, 6 -physical therapists, 1 -neurologist, 2 -Primary Care Physicians, 1 -homeopath, 2 -“health practitioners”, and the rest “remained unreported”.[4][5][6] Admittedly there is inherent risk, albeit minimal, associated with neck manipulation but all forms of therapeutic intervention come with risk and some are far greater than SMT.

 Take for instance the most common “quick fix” for musculoskeletal pain, non-steroidal anti-inflammatories [NSAIDs] (i.e. Advil, Aleve, Motrin, Tylenol). Medical studies published during the 1990s found that hospitalizations due to gastrointestinal complications from NSAIDs range from 32,000 - 103,000 while NSAID related deaths average out at 9,850 ANNUALLY in the United States alone![7][8][9] In fact the Food and Drug Administration reports that the largest cause of drug overdose in the United States is acetaminophen (Tylenol) which by itself is responsible for 56,000 emergency room visits, 2,600 hospitalizations, and 458 deaths due to acute liver failure EVERY YEAR![10] The one-year risks of experiencing complications due to prolonged NSAID use are simply staggering: [11]

Severe gastrointestinal bleeding:

            - Adults younger than 45 = 1 in 2,100

            - Adults older than 75 = 1 in 110

Death:

            - Adults younger than 45 = 1 in 12,353

            - Adults older than 75 = 1 in 647

These non-prescription pain relievers have become an accepted form of musculoskeletal pain relief yet their catastrophic effects have never been as scrutinized as spinal manipulative therapy which has been scientifically proven to be more effective in relieving neck pain and headache[12] with statistically infinitesimal risk of serious adverse reaction.

A population based study published in Neurology in 2006 discovered that over a 16 year period (1987-2003) the incidence rate of  strokes due to arterial dissection (ICAD and VAD) affected only 0.97 - 1.72 residents per 100,000 annually within the defined community (Olmsted County, MN).[13] These findings regarded the population in general since reliable epidemiological data was not available. A subsequent population-based case control and case-crossover study conducted by members of the Bone and Joint Decade 2000-2010 Task Force on Neck Pain and Its Associated Disorders was published in SPINE in 2008 which investigated the association between chiropractic care and stroke due to arterial dissection and compared it to primary care physician (PCP) treatment for the same issue.[14] This study examined ALL residents of Ontario (109,020,875 person years), Canada’s most populous province over a nine (9) year period (1993-2002). The researchers found only 818 cases of stroke due to arterial dissection that met the study’s inclusion/exclusion criteria. Overall, 4.4% (n=36) of the cases had visited a chiropractor and 51.0% (417) had only visited a PCP 30 days prior to hospital admission for stroke related to arterial dissection. It should be noted  though that of the 36 cases noted above, only 16 cases (2.0%) were exclusively chiropractic visits 20 (2.4%) had visited both a chiropractor and PCP with the remaining 365 cases having consulted no one for care prior to hospitalization due to stroke. In the end the researchers came to the following conclusions:

            - Stroke due to arterial dissection within the population is a RARE EVENT.

- Of the 453 cases that did consult either a chiropractor or PCP prior to hospitalization, the chief complaint upon presentation was neck pain and headache. The researchers concluded that this similarity was due to an arterial dissection IN PROGRESS which led these patients to seek relief of their pain.

- There is an association between chiropractic care and arterial dissection-related stroke within residents under the age of 45 but chiropractic care DOES NOT exhibit any excess risk of eliciting a stroke.

- There is an association in PCP care and arterial dissection-related stroke in ALL AGE GROUPS.

- Currently there exists no valid screening procedure to identify the risk of stroke in a person presenting with neck pain and/or headache.

The substantive nature of this data is enlightening but in no way exhausts the need for further investigation into this rare yet life altering event. A collaborative effort between chiropractors and neurologists during future research is needed in order to derive a feasible screening method and eliminate the confusing and conflicting information currently being given to patients regarding the treatment of neck pain and headache.

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[1] Haldeman, Scott, Paul Carey, Murray Townsend, and Costa Papadopoulos. "Arterial Dissections following Cervical Manipulation the Chiropractic Experience." Canadian Medical Association Journal 165.7 (2001): 905-06. Print.

[2] Cassidy, David, Eleanor Boyle, Pierre Cote, Helen He, Sheilah Hogg-Johnson, Frank L. Silver, and Susan J. Bondy. "Risk of Vertebrobasilar Stroke and Chiropractic Care." Spine 33.4S (2008): 000. Print.

[3] Terrett, AG. "Misuse of the Literature by Medical Authors in Discussing Spinal Manipulative Therapy Injury." Journal of Manipulative and Physiological Therapeutics 18.4 (1995): 203-10. Print.

[4] Murphy, Donald. “Primary Spine Practitioner Training Session III: Putting it all Together.” Community Spine Pathway Training. Burgundy Basin Inn, Rochester. 3&4 May 2014. Lecture.

[5] Hufnagel, A., Alexander Hammers, Paul-Walter Schonle, Klaus-Dieter Bohm, and Georg Leonhardt. "Stroke following Chiropractic Manipulation of the Cervical Spine." Journal of Neurology 246(8) (1999): 683-88. Print.

[6] Reuter, U., M. Hamling, I. Kavuk, K. M. Einhaupl, and E. Schielke. "Vertebral Artery Dissections after Chiropractic Neck Manipulation in Germany over Three Years." Journal of Neurology 253(6) (2006): 724-30. Print.

[7] Risser, Amanda, Deirdre Donovan, John Heintzman, and Tanya Page. "NSAID Prescribing Precautions." American Family Physician 80.12 (2009): 1371-378. American Academy of Family Physicians. American Family Physician, 15 Dec. 2009. Web. 08 May 2014. <http://www.aafp.org/afp/2009/1215/p1371.html#afp20091215p1371-b13>.

[8] Wolfe, Micheal, David Lichtenstein, and Gurkirpal Singh. "Gastrointestinal Toxicity of Nonsteroidal Anti-inflammatory Drugs." New England Journal of Medicine 340;24 (1999): 1888-899. Print.

[9] Tarone RE, Blot WJ, McLaughlin JK. Nonselective non-aspirin nonsteroidal anti-inflammatory drugs and gastrointestinal bleeding. Am J Ther. 2004;11(1):17–25.

[10] June 29-30, 2009: Joint Meeting of the Drug Safety and Risk Management Advisory Committee with the Anesthetic and Life Support Drugs Advisory Committee and the Nonprescription Drugs Advisory Committee: Meeting Announcement http://www.fda.gov/AdvisoryCommittees/Calendar/ucm143083.htm).

[11] Blower AL, Brooks A, Fenn GC, et al. Emergency admissions for upper gastrointestinal disease and their relation to NSAID use. Aliment Pharm Ther. 1997;11(2):283–291.

[12] Association, American Chiropractic. "Benefits and Risks of Neck Pain Treatments." Acatoday.org. American Chiropractic Association, n.d. Web. 13 May 2014. <http://www.acatoday.org/pdf/Benefits_Risks_Neck_Pain_Treatments.pdf>.

[13] Lee, VH, Brown RD Jr, Mandrekar JN, et al. Incidence and outcome of cervical artery dissection: a population-based study. Neurology 2006;67: 1809-12

[14]Cassidy, David, Eleanor Boyle, Pierre Cote, Helen He, Sheilah Hogg-Johnson, Frank L. Silver, and Susan J. Bondy. "Risk of Vertebrobasilar Stroke and Chiropractic Care." Spine 33.4S (2008): 000. Print.