The Palmer Center for Chiropractic Research,
headquartered on the Palmer College of
Chiropractic campus in Davenport, is the
largest institutional chiropractic research
effort in the world.
Summary: Vertebral artery (VBA) dissection and stroke are
very rare and generally occur with no obvious cause.
Headache and neck pain are common symptoms of VBA
dissection, preceding an estimated >80 percent of VBA
strokes. These symptoms may precipitate the patient to
seek medical physician/chiropractic treatment.
Cassidy et al., (2008) analyzed the records of 818 patients
who were hospitalized with VBA strokes in Ontario hospitals
(April 1, 1993 to March 31, 2002) to determine if an
association existed between chiropractic visits and VBA
stroke or primary care physician visits and VBA stroke. Of
the 818 cases, 54.2 percent were categorized as vertebral
occlusion and stenosis, 41.2 percent were coded as basilar
occlusion and stenosis, and 4.7 percent had both codes.
In patients under age 45, there was an increased association
between both chiropractic and medical physician visits
(within the month prior to) and VBA stroke. In patients
older than 45, no increased association between VBA
strokes and chiropractic visits were found. In addition,
the authors found no increase in risk associated with
chiropractic treatment when compared to treatment by a
Take-home Message: There doesn’t appear to be an increased
risk of VBA stroke associated with chiropractic care
when compared to medical physician visits. The association
between VBA stroke and both chiropractor and medical
doctor visits is most likely explained by patients with
neck pain and headache seeking relief from health-care
providers before their VBA stroke.
Practical Applications for Chiropractors: It’s important to think about the possibility
of VBA when a patient presents with
headache and neck pain. Once should also
be aware of confounding factors, which may
increase the risk of VBA stroke, such as obesity,
smoking and untreated hypertension,
and screen for undiagnosed vertebral artery
dissection when appropriate.