Cervical manipulations have been associated with vascular complications. While the incidence of carotid dissections does not seem to have increased, the question remains open for vertebral artery injuries. We must remain vigilant!
Resorting to joint manipulation for neck pain is not unusual. Currently, cervical manipulation remains a popular first-line treatment for cervicodynia or headaches. Although evidence exists showing that specific joint mobilization can improve this type of symptomatology, there is a possibility that it may risk damaging the cervical arteries and causing ischemic stroke through arterial dissection.
Epidemiologically, internal carotid artery dissection is a relatively rare event with an estimated annual incidence of 1.72 per 100,000 individuals (those most likely to be diagnosed being obviously those leading to hospitalization for stroke) but represents one of the most common causes of stroke in young and middle-aged adults. Faced with case reports that may raise concerns and hypotheses about an associated risk, two studies have sought to delve into the issue.
No Increased Carotid Risk Identified
The first study, of a case-cross design, identified all incident cases of ischemic stroke in the territory of the internal carotid artery admitted to the hospital over a 9-year period using administrative healthcare data, the cases being used as their own control by sampling control periods before the date of the index stroke. Thus, 15,523 cases were compared with 62,092 control periods using exposure windows of 1, 3, 7, and 14 days before the stroke. The study also compared post-medical consultation and post-chiropractic consultation outcomes, knowing that as a first-line for complaints of neck pain or headache, patients often turn to one of these two types of primary care clinicians.
However, data analysis shows, among subjects aged under 45 years, positive associations for both different consultations in cases of subsequent carotid stroke (but no association for those aged over 45 years). These associations tended to increase when analyses were limited to visits for diagnoses of neck pain and headaches. Nevertheless, there was no significant difference between risk estimates after chiropractic or general medical consultation.
A notable limitation of this work is that it did not focus on strokes due to vertebral artery dissections that run through the transverse foramina of the cervical vertebrae.
A Screening Test Lacking Precision
More recently, the International Federation of Orthopedic Manual Physical Therapists has looked into the subject to refine the assessment of the risk for vascular complications in patients seeking physiotherapy/osteopathy care for neck pain and/or headaches. Through a cross-sectional study involving 150 patients, it tested a vascular complication risk index (from high to low grade, based on history taking and clinical examination), developed to estimate the risk for the presence of vascular rather than musculoskeletal pathology, to determine whether or not there is a contraindication to cervical manipulation.
However, the developed index had only low sensitivity (0.50; 95% CI, 0.39-0.61) and moderate specificity (0.63; 95% CI, 0.51-0.75), knowing that the reference test was a consensus medical decision made by a vascular neurologist, an interventional neurologist, and a neuroradiologist (based on clinical data and cervical MRI). Similarly, positive and negative likelihood ratios were low at 1.36 (95% CI, 0.93-1.99) and 0.79 (95% CI, 0.60-1.05), respectively.
In conclusion, the data from the case-cross study did not seem to demonstrate an excess risk for stroke in the territory of the internal carotid artery after cervical joint manipulations. Associations between cervical manipulation sessions or medical consultations and carotid strokes appear similar and could have been due to the fact that patients with early symptoms related to arterial dissection seek care before developing their stroke.
However, it is regrettable that the study did not focus on vertebral artery dissections, which are anatomically more exposed to cervical chiropractic sessions. Nevertheless, because indices defined from joint tests and medical history are insufficient to identify patients “at risk or in the process of arterial dissection,” and because stroke can result in severe disability, practitioners managing patients with neck pain cannot take this type of complication lightly.
This story was translated from JIM using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.