Clinical updateThe etiology of cervical artery dissection
Introduction
The etiology of cervical artery dissection (CAD) is, for the most part, unclear; and what has been proposed as an explanation for its pathogenesis is largely hypothetical.1 Furthermore, when dealing with a particular case of CAD, the pathogenesis is especially speculative.2 Nevertheless, a number of risk factors have been reported to be associated with the condition, including connective tissue abnormalities, hypertension, recent infection, migraine headache, the use of oral contraceptives, and others. Of special interest to chiropractors is the role cervical spine manipulation (CSM) plays, if any, in the pathogenesis of CAD. Indeed, patients do experience CAD on rare occasions after CSM, making knowledge about the cervical arteries, the predisposing factors, and the pathogenesis of the condition important for chiropractors.
Section snippets
Anatomy of the cervical arteries
The understanding of CAD is greatly enhanced by having a basic grasp of the relevant anatomy. A pair of vertebral arteries (VAs) and a pair of internal carotid arteries (ICAs) pass through the cervical region to supply the brain with blood. The ICAs and their branches are often referred to as the anterior circulation because they supply blood to the anterior portion of the brain. The vertebral and basilar arteries comprise the vertebrobasilar system, which is referred to as the posterior
Mechanisms of dissection
The VA seems most susceptible to strain in the atlantal segment as it traverses the C1-2 articulation,30 where it seems most at risk during rotational movements.6 The proposed mechanism of arterial strain during neck rotation involves the ipsilateral C1-2 joint being fixed while the contralateral side of C1 is propelled forward, which compresses and stretches the artery. The ICA is most susceptible to strain in the upper cervical region when the head and neck are in combined rotation or lateral
Conclusion
The cervical arteries are susceptible to dissection in association with a variety of trivial events. This association is confusing, however, because people normally encounter innumerable trivial events during their lifetime without ever experiencing dissection. Moreover, patients do not live in a vacuum and are typically exposed to other potentially contributory incidents before and after an event that is suspected of causing a particular CAD. For instance, they turn their heads to back up
References (90)
- et al.
Dissections of cervical and cerebral arteries
Neurol Clin
(1983) - et al.
Causes of complications from cervical spine manipulation
Aust J Physiother
(2001) - et al.
An analysis of the etiology of cervical artery dissections: 1994 to 2003
J Manipulative Physiol Ther
(2005) - et al.
Bilateral internal carotid artery dissection from vomiting
Am J Emerg Med
(1998) - et al.
Cervical artery dissection. A comparison of highly dynamic mechanisms: manipulation versus motor vehicle collision
J Manipulative Physiol Ther
(2005) - et al.
Arterial fibromuscular dysplasia
Mayo Clin Proc
(1987) - et al.
Spontaneous vertebral artery dissection as a complication of autosomal dominant polycystic kidney disease
Am J Kidney Dis
(1995) Spontaneous cervical artery dissections and implications for homocysteine
J Manipulative Physiol Ther
(2004)- et al.
Carotid and vertebral artery dissection syndromes
Postgrad Med J
(2005) Spontaneous dissection of the carotid and vertebral arteries
N Engl J Med
(2001)
Volume 1: nervous system. Part 1: anatomy and physiology
The complexity of trauma to the cranio-cervical junction: correlation of clinical presentation with Doppler flow velocities in the V3-segment of the vertebral arteries
Acta Neurochir (Wien)
The vertebral artery: its relationship with adjoining tissues in its course intra and inter transverse processes in man
Rev Paul Med
Injury of the carotid and vertebral arteries
Neuroradiology
Fibromuscular dysplasia: multiple “spontaneous” dissecting aneurysms of the major cervical arteries
Ann Neurol
Traumatic dissection of the extracranial internal carotid artery
Neurosurgery
Extracranial and intracranial vertebrobasilar dissections: diagnosis and prognosis
J Neurol Neurosurg Psychiatry
Carotid dissection with and without ischemic events: local symptoms and cerebral artery findings
Neurology
Pain as the only symptom of cervical artery dissection
J Neurol Neurosurg Psychiatry
Identification of internal carotid artery dissection in chiropractic practice
J Can Chiropr Assoc
Spontaneous dissection of the cervical internal carotid artery
Ann Neurol
Internal carotid artery dissection
Acta Neurol Scand
Spontaneous dissection of the internal carotid artery
Arch Surg
Generalized arteriopathy in patients with cervical artery dissection
Neurology
Dissecting hematoma of the internal carotid artery following chiropractic cervical manipulation
J Trauma
Mechanism of ischemic infarct in spontaneous carotid dissection
Stroke
Aneurysmal forms of cervical artery dissection: associated factors and outcome
Stroke
Vertebral artery dissection due to indirect neck trauma: an underrecognised entity
Neurol India
The treatment of spontaneous carotid and vertebral artery dissections
Curr Opin Cardiol
Internal carotid artery dissection in a community. Rochester, Minnesota, 1987-1992
Stroke
Incidence of internal carotid artery dissection in the community of Dijon
J Neurol Neurosurg Psychiatry
Association of internal carotid artery dissection and chiropractic manipulation
Neurolog
Cervical artery dissection-clinical features, risk factors, therapy and outcome in 126 patients
J Neurol
Unpredictability of cerebrovascular ischemia associated with cervical spine manipulation therapy: a review of sixty-four cases after cervical spine manipulation
Spine
Stroke following chiropractic manipulation of the cervical spine
J Neurol
Blunt carotid injury. Importance of early diagnosis and anticoagulant therapy
Ann Surg
Spontaneous dissection of the internal carotid artery
Acta Chir Scand
Manipulation of the cervical spine: risks and benefits
Phys Ther
Vertebrobasilar ischemia after neck motion
Stroke
Motor vehicle accidents: the most common cause of traumatic vertebrobasilar ischemia
Can J Neurol Sci
Spontaneous dissection of the internal carotid artery in 68 patients
Eur J Med
Pain, dizziness, and central nervous system blood flow in cervical extension: vascular correlations to beauty parlor stroke syndrome and salon sink radiculopathy
Am J Phys Med Rehabil
Perspectives: an overview of comparative considerations of cerebrovascular accidents
Chirpr J Aust
Cited by (26)
Changes in Vertebral Arterial Blood Flow During Premanipulative Tests in Participants With Upper Cervical Spine Motion Restriction
2020, Journal of Manipulative and Physiological TherapeuticsCitation Excerpt :When this condition is met, the combined VFR (62 + 30 = 92 mL/min) may drop below the cutoff value for ischemia (100 mL/min).22 Vertebral artery dissection like hypoplasia also causes arterial narrowing.26 Zaina et al3 noted a trend of decreasing VFR in the left VA at C5-C6 at end-range rotation.
Cervical artery dissections: Factors that influence causation determination in litigated cases
2018, Journal of Forensic and Legal MedicineCitation Excerpt :However, the intensity of the trauma necessary to initiate the lesion remains a question of debate especially when low-energy injuries are involved. Many authors hypothesize that given the large occurrence of neck movements in all sorts of activities and the high frequency of infection in the population, minor traumas do not cause CAD in most individuals.11,17,18 According to these authors, people who undergo a CAD with or without minor trauma likely have an underlying pathological process, be it an arteriopathy, an inflammation, or structural weakness of the artery wall that leads to dissection.
Operative management of catastrophic bleeding in the head and neck
2017, Operative Techniques in Otolaryngology - Head and Neck SurgeryRisk of stroke after chiropractic spinal manipulation in Medicare B beneficiaries aged 66 to 99 years with neck pain
2015, Journal of Manipulative and Physiological TherapeuticsCitation Excerpt :Similarly, a review published in 2012 found the evidence inadequate to either confirm or refute a significant association between manipulation of the cervical spine and stroke.13 Efforts to identify either risk factors or populations at risk for VBS have been largely unsuccessful.14,15 The risk of stroke in general increases with age,16 but it is not known how age might affect the risk of stroke after spinal manipulation.17