IMPLICATIONS OF OUR FINDINGS
Over a 4-year period at our institution, 12 patients experienced cervical vessel dissection related to chiropractic neck manipulation. A similar institution in another part of the country had previously described 13 such cases. The patients at both institutions were relatively young and incurred substantial residual morbidity. A single patient at each institution died. If these findings are representative of other institutions across the United States, the incidence of stroke secondary to chiropractic manipulation may be higher than supposed.
To assess this problem further, a randomized prospective cohort study could establish the relative risk of chiropractic manipulation of the cervical spine resulting in a cervical artery dissection. But such a study may be methodologically prohibitive. More feasible would be a case-control study similar to one carried out by Smith et al5 in which patients who had experienced cervical artery dissection were matched with subjects who had not incurred such injuries. Comparing the groups’ odds of having received chiropractic manipulation demonstrated that spinal manipulative therapy is an independent risk factor for vertebral artery dissection and is highly suggestive of a causal association. Replicating this study in a different population would be valuable.
Based on our findings, all patients who visit chiropractors for cervical spine manipulation should be informed of the potential risks and of the need to seek immediate medical assistance should symptoms suggestive of dissection or stroke occur during or after manipulation. Until the actual level of risk from chiropractic manipulation is known, patients with neck pain may be better served by equally effective passive physical therapy exercises.1
CORRESPONDENCE
Raymond E. Bertino, MD, 427 West Crestwood Drive, Peoria, IL 61614; rebertino@comcast.net.
ACKNOWLEDGEMENTS
We thank Deepak Nair, MD, for his assistance in reviewing the stroke neurology aspects of this study; Katie Groesch, MD, for her assistance in drafting portions of the Methods and Results sections; Rita Hermacinski for the generation of 3D images; and Stephanie Arthalony for her assistance in gathering information through patient telephone interviews.