As I understand the story, Ms. May felt she had a pinched nerve in her neck after a photo shoot and sought the help of her chiropractor. It is my understanding that she saw him 3 times and the reports are that he adjusted her and provided mechanical traction. We don’t know what kind of adjustment technique he used or which of the cervical vertebrae he adjusted. We don’t know what mechanical traction means. We don’t know what else he may have done during those visits. We also don’t know if Ms. May had any predispositions to dissection. We don’t know about her other activities prior to the dissection. There are rumors of her taking a fall during the photo shoot but that has since been discredited. And we don’t know exactly when the dissection time-line began. There is much we just don’t know. We do know that her symptoms worsened over days eventually effecting cognition, speech, and balance, and that she was taken to the E.R. where treatment failed to prevent her death. What we have here is a tragedy on multiple fronts. A beautiful life has been lost, a family has been left mourning and wanting answers, a doctor’s career and reputation is on the line, and the safety of an entire profession, or at least a procedure within that profession, has been called into question.
Again, that was February. In October the coroner released his report which states that the cause of death was brain infarction due to cervical artery dissection (CAD) caused by chiropractic manipulation of the cervical spine. With ironic timing, the same month that Ms. May died, a report was published by six neurosurgeons representing three University medical centers. You can find the entire publication at http://www.cureus.com/articles/4155-systematic-review-and-meta-analysis-of-chiropractic-care-and-cervical-artery-dissection-no-evidence-for-causation. They conclude, “There is no convincing evidence to support a causal link between chiropractic manipulation and CAD.” They go on, “Belief in a causal link may have significant negative consequences such as numerous episodes of litigation.” Kosloff published results of an American study in 2015 and Cassidy a Canadian study in 2008, neither of which found a causal relationship between CAD and chiropractic. Kosloff concluded, “We found no significant association between exposure to chiropractic care and the risk of VBA stroke. We conclude that manipulation is an unlikely cause of VBA stroke. The positive association between PCP visits and VBA stroke is most likely due to patient decisions to seek care for the symptoms (headache and neck pain) of arterial dissection. We further conclude that using chiropractic visits as a measure of exposure to manipulation may result in unreliable estimates of the strength of association with the occurrence of VBA stroke.”
What Kosloff and all the other studies on this subject are saying is that although there is a “temporal association” between CAD and chiropractic there is no “causal association.” This makes perfect sense. The primary symptoms of CAD are headache and neck pain, symptoms I see every hour in my practice. If you are a chiropractic patient and you develop a dissection causing neck pain, you will probably seek the help of your chiropractor. Sadly, there are no reliable screening procedures to rule out dissection as opposed to mechanical neck pain (what chiropractors call vertebral subluxation complex). There might be subtle clues from the patient’s report of the character of their pain that might trigger a red flag for the clinician, initiating referral to the E.R., but since CAD is so rare and neck pain and headache are so common, the clinician is likely going to treat the patient just as he always has, with an adjustment. If the condition is a dissection, it will progress in spite of the adjustment, not because of the adjustment, and the patient will end up in the E.R. once cognitive symptoms begin. And had the patient gone to his/her medical doctor and been prescribed Ibuprofen, the patient would be in the same position later, again, in spite of, not because of the Ibuprofen.
So what are the real risks? A study by Croft, et.al. published in 2002 found a mere 117 cases of post-manipulation ischemia(loss of blood flow) in all of the English-language scientific literature in the past 150 years. It is extremely rare. A RAND Corp. study put the risk of CAD associated with chiropractic manipulation at 1 in every 1.46 million patient visits. A Danish study similarly put the risk at 1 in every 1.3 million patient visits. This puts the risk of you having a cervical artery dissection associated with a chiropractic visit at less than 0.0001%, which is the exact same rate of cervical artery dissection in the general population. In other words, you are at the same statistical risk of CAD if you seek chiropractic care, medical care, or do nothing.
So where do we go from here? There is no evidence that chiropractic manipulation causes CAD. The risk of CAD following manipulation is the same as the risk of CAD anywhere else. The fact is that the story of Katie May is news worthy because it is so rare, and helps to feed an anti-chiropractic agenda. I’m not implying the coroner is anti-chiropractic. I’m sure he is just doing his job, but perhaps ignoring science. Regardless, there is a long history of bias against my profession by some in the medical profession. As proof, on September 25, 1987, Judge Getzendanner (7th circuit court of appeals) issued her opinion that the AMA had violated Section 1 of the Sherman Anti-trust Act, and that it had engaged in an unlawful conspiracy in restraint of trade "to contain and eliminate the chiropractic profession." (Wilk v. American Medical Ass'n, 671 F. Supp. 1465, N.D. Ill. 1987). She further stated that the "AMA had entered into a long history of illegal behavior". I contrast this to the fact that mortality rate from the combination of medical mistakes, drug interactions, opioid addiction, and hospital-born infections makes the practice of medicine the 3rd leading cause of death in the U.S. This is well established but ignored in the news cycle. It’s just another statistic, and not headline grabbing.
I have never had a case of CAD in my practice, but I still pay attention to the character of my patients’ complaints to look for the rare red flag. I pray I will be wise enough to see it if it ever crosses my threshold. In the meantime I will continue to teach my patients about the wonderful benefits of chiropractic care. I will continue to inform them of the real risks of chiropractic, which are blessedly few. I will continue to provide quality chiropractic adjustments to my hundreds of patients. I will go to my chiropractor for treatment of my neck. When my wife, children and grandchildren complain of neck pain and headache, I will adjust them. Lastly, I will hope that science will trump headlines and the truth of this most recent incident will come to light. If this chiropractor did something to his patient that no other chiropractor in the history of my profession has done, and caused a CAD, then let the chips fall where they may. If he ignored blatant and obvious signs of a dissection in progress and chose to not refer to the E.R. then he deserves punishment. But if he is just the unlucky clinician who was simply the last doctor to see a poor girl who was moving irrevocably toward death, then his name needs to be cleared. Regardless, chiropractic as a profession can hold its head high and know that what we do is extremely safe, and far far safer than any medical alternative.