Do Chiropractors Cause Strokes?

In recent years stories have made headlines accusing chiropractors of causing strokes. This has led some to hesitate before seeking out chiropractic care, but is there actually a risk of stroke associated with a chiropractic adjustment?

Before we jump right into this, it’s important to understand that there are different types of stroke. The two major classifications of stroke are Hemorrhagic and Ischemic. Hemorrhagic strokes are the result of a ruptured blood vessel. The most common type of hemorrhagic stroke is an intracerebral stroke, where the ruptured vessel is within the brain itself. The second type of hemorrhagic stroke is termed subarachnoid hemorrhage. This happens when the ruptured vessel is located within the membranes that cover the brain and is usually the result of an aneurysm.  Ischemic strokes on the other hand, occur when blood clots or various “debris” in the blood occludes a vessel and prevents blood from getting to the brain. According to the National Institutes of Health, 87% of strokes are Ischemic and 13% are hemorrhagic. 1  

Chiropractors have been accused of damaging a blood vessel in the neck called the vertebral artery, which is one of the vessels carrying blood to the brain. The specific injury they have been accused of causing is termed “vertebral artery dissection”, or a tear on the inside of the artery wall that can lead to blood clot formation and can cause an ischemic stroke. Vertebral artery dissection can be the result of head and neck trauma, from car accidents and similar types of injuries, and can even happen spontaneously in individuals with connective tissue disorders or those with vascular risk factors. 

In 2023 researchers at the University of Calgary conducted a study to understand if there was enough force being applied to vertebral arteries during a chiropractic adjustment to cause damage to the vessels. In the study they used seven cadavers as their test subjects and measured the amount of tensile force throughout the vertebral arteries while they moved every bone in the neck 516 separate times in a manner similar to a chiropractic adjustment. The researchers concluded that the vertebral arteries do not experience any tensile force during a chiropractic adjustment.2 This means that it is impossible for chiropractors to cause the type stroke they have been accused of. 

In 2022 U.S. Federal Medicare completed a retrospective claims analysis study in one of the largest sample sizes of any study ever! After reviewing 53,684,265 Medicare beneficiaries that were included in the study, the researchers concluded that Medicare beneficiaries age 65 and older who received cervical spine adjustments were at no greater risk of cervical artery dissection than control groups.3

So, if it’s not physically possible for a chiropractic adjustment to cause a stroke, then why have these stories made national headlines? The two most common early symptoms of stroke are neck pain and headache, which also happen to be two of the most common reasons people seek out chiropractic care.

 If a person with neck pain goes to a medical doctor they will likely be given a prescription pain killer, anti-inflammatory, and muscle relaxer. If a person with neck pain goes to a chiropractor they will likely be adjusted. If that neck pain is a symptom of a stroke it’s a much more sensational story for the media to attempt to attribute that stroke to the chiropractic adjustment than it would be to attribute it to the prescription drugs given by the medical doctor – even though the National Institutes for Health say that the risk of stroke after seeing a chiropractor is the same as after seeing a medical doctor. 4

What can you do to minimize your risk of stroke?

Some of the most common and controllable risk factors associated with stroke are: 

  • high blood pressure 
  • diabetes 
  • smoking
  • Use of birth control
  • excessive alcohol consumption 
  • obesity 
  • Lack of physical activity
  • Recreational drug use

Interestingly enough, research has shown that chiropractic care can be beneficial for several of the risk factors associated with stroke. This includes: improving blood pressure5, reducing inflammation, improving circulation, and reduction cardiovascular stress through improved balance of the autonomic nervous system. In fact, a 2023 study reviewed 1,851 patient files concluded that primary role of chiropractic care may be preventative healthcare.6 If you’re concerned about lowering your risk of stroke it’s important to control what you can, and chiropractic care can be a great tool to help.   

Sources

  1. Abdu H, Tadese F, Seyoum G. Comparison of Ischemic and Hemorrhagic Stroke in the Medical Ward of Dessie Referral Hospital, Northeast Ethiopia: A Retrospective Study. Neurol Res Int. 2021 Jun 28;2021:9996958.
  2. Gorrell LM, Sawatsky A, Edwards WB, Herzog W. Vertebral arteries do not experience tensile force during manual cervical spine manipulation applied to human cadavers. J Man Manip Ther. 2023 Aug;31(4):261-269.
  3. Whedon JM, Petersen CL, Li Z, Schoelkopf WJ, Haldeman S, MacKenzie TA, Lurie JD. Association between cervical artery dissection and spinal manipulative therapy -a medicare claims analysis. BMC Geriatr. 2022 Nov 29;22(1):917.
  4. Phillips RB, Lukovits TG, Lurie JD. Risk of stroke after chiropractic spinal manipulation in medicare B beneficiaries aged 66 to 99 years with neck pain. J Manipulative Physiol Ther. 2015 Feb;38(2):93-101.
  5. Bakris G, Dickholtz M Sr, Meyer PM, Kravitz G, Avery E, Miller M, Brown J, Woodfield C, Bell B. Atlas vertebra realignment and achievement of arterial pressure goal in hypertensive patients: a pilot study. J Hum Hypertens. 2007 May;21(5):347-52.
  6. Kwon C, Binongo JN, McCoy M. Secondary Analysis of a Dataset to Estimate the Prevalence of Vertebral Subluxation and Its Implications for Health Promotion and Prevention. Cureus. 2023 Nov 13;15(11)