Craniocervical arterial dissections as sequelae of chiropractic manipulation: patterns of injury and management.

OBJECT: Chiropractic manipulation of the cervical spine is a known cause of craniocervical arterial dissections. In this paper, the authors describe the patterns of arterial injury after chiropractic manipulation and their management in the modern endovascular era. METHODS: A prospectively maintained endovascular database was reviewed to identify patients presenting with craniocervical arterial dissections after chiropractic manipulation. Factors assessed included time to symptomatic presentation, location of the injured arterial segment, neurological symptoms, endovascular treatment, surgical treatment, clinical outcome, and radiographic follow-up. RESULTS: Thirteen patients (8 women and 5 men, mean age 44 years, range 30-73 years) presented with neurological deficits, head and neck pain, or both, typically within hours or days of chiropractic manipulation. Arterial dissections were identified along the entire course of the vertebral artery, including the origin through the V(4) segment. Three patients had vertebral artery dissections that continued rostrally to involve the basilar artery. Two patients had dissections of the internal carotid artery (ICA): 1 involved the cervical ICA and 1 involved the petrocavernous ICA. Stenting was performed in 5 cases, and thrombolysis of the basilar artery was performed in 1 case. Three patients underwent emergency cerebellar decompression because of impending herniation. Six patients were treated with medication alone, including either anticoagulation or antiplatelet therapy. Clinical follow-up was obtained in all patients (mean 19 months). Three patients had permanent neurological deficits, and 1 died of a massive cerebellar stroke. The remaining 9 patients recovered completely. Of the 12 patients who survived, radiographic follow-up was obtained in all but 1 of the most recently treated patients (mean 12 months). All stents were widely patent at follow-up. CONCLUSIONS: Chiropractic manipulation of the cervical spine can produce dissections involving the cervical and cranial segments of the vertebral and carotid arteries. These injuries can be severe, requiring endovascular stenting and cranial surgery. In this patient series, a significant percentage (31%, 4/13) of patients were left permanently disabled or died as a result of their arterial injuries.

The biomechanics of spinal manipulation.

Biomechanics is the science that deals with the external and internal forces acting on biological systems and the effects produced by these forces. Here, we describe the forces exerted by chiropractors on patients during high-speed, low-amplitude manipulations of the spine and the physiological responses produced by the treatments. The external forces were found to vary greatly among clinicians and locations of treatment on the spine. Spinal manipulative treatments produced reflex responses far from the treatment site, caused movements of vertebral bodies in the "para-physiological" zone, and were associated with cavitation of facet joints. Stresses and strains on the vertebral artery during chiropractic spinal manipulation of the neck were always much smaller than those produced during passive range of motion testing and diagnostic procedures.

[The implications of cervical spine degenerative and traumatic diseases in the pathogenesis of cervical vertigo and hearing loss]. / Implicatiile bolilor degenerative si traumatice ale coloanei cervicale in geneza vertijului cervical si a hipoacuziei.

AIM: Cervical spine together with vestibular system,visual system and proprioceptive afferents plays an important role in mentaining balance. Spine damage causes distortions in transmitting informations to the brain,favoring vertigo. MATERIAL AND METHOD: The authors point out the occurrence of positional vertigo on 23 patients (20 patients with cervical spondylosis and 3 patients with cervical spine injury) due to blood flow disturbance through vertebral artery. RESULTS: The mechano-receptors located in intervertebral disks and cervical spine muscles are activated by column movement. Changes of blood flow in the vertebral and basilar arteries are showed up by cervical X-Rays, intracranial Doppler ultrasound or angio-MRI, an audiogram marking out the degree of hearing loss or tinnitus occurence. ENT complex treatment outcomes are analyzed and balneo-physio-therapy performed in order to improve vertigo and hearing loss. CONCLUSIONS: Stress beside muscle overload and cervical spine injures causes alteration in the ear blood-flow circulation that leads to hearing loss, vertigo and tinnitus. It emphasies the need for collaboration between balneologist and ENT specialist in solving balance and hearing disorders with cervicogenic cause.

Iatrogenic vertebral artery injury.

Iatrogenic vertebral artery injury (VAI) results from various diagnostic and therapeutic procedures. The objective of this article is to provide an update on the mechanism of injury and management of this potentially devastating complication. A literature search was conducted using PubMed. The iatrogenic VAIs were categorized according to each diagnostic or therapeutic procedure responsible for the injury, i.e., central venous catheterization, cervical spine surgery, chiropractic manipulation, diagnostic cerebral angiography, percutaneous nerve block, and radiation therapy. The incidence, mechanisms of injury, and reparative procedures were discussed for each type of procedure. The type of VAI depends largely on the type of procedure. Laceration was the dominant type of acute injury in central venous catheterization and cervical spine surgery. Arteriovenous fistulae and pseudoaneurysms were the delayed complications. Arterial dissection was the dominant injury type in chiropractic manipulation and diagnostic cerebral angiography. Inadvertent arterial injection caused seizures or stroke in percutaneous nerve block. Radiation therapy was responsible for endothelial injury which in turn resulted in delayed stenosis and occlusion of the vertebral artery (VA). The proximal VA was the most vulnerable portion of the artery. Although iatrogenic VAIs are rare, they may actually be more prevalent than had previously been thought. Diagnosis of iatrogenic VAI may not always be easy because of its rarity and deep location, and a high level of suspicion is necessary for its early detection. A precise knowledge of the surgical anatomy of the VA is essential prior to each procedure to prevent its iatrogenic injury.

Cervical artery dissection. A comparison of highly dynamic mechanisms: manipulation versus motor vehicle collision.

OBJECTIVE: To examine the similarities and dissimilarities between cervical chiropractic manipulative therapy and whiplash, and their respective relation to cervical artery dissection. DATA SOURCES: A literature synthesis used MEDLINE-PubMed and MANTIS literature searches. A total list of 99 relevant articles was generated. Additional references were collected from citations incorporated within the included articles. RESULTS: Both neck manipulation and motor vehicle collision events apply loads to the spinal column rapidly. While neck manipulation loads are slower to develop and displacements smaller, they may reach peak amplitudes on maximum effort comparable to those seen in low-velocity collision experiments. In contrast to reports that the vertebral artery experiences elongations exceeding its physiological range by up to 9.0 mm during simulated whiplash, strains incurred during cervical manipulative therapy have been reported to be approximately one ninth of those required for mechanical failure, comparable to forces encountered in the course of diagnostic range of motion examination. Additionally, long-lasting abnormalities of blood flow velocity within the vertebral artery have been reported in patients following common whiplash injuries, whereas no significant changes in vertebral artery peak flow velocity were observed following cervical chiropractic manipulative therapy. CONCLUSIONS: Perceived causation of reported cases of cervical artery dissection is more frequently attributed to chiropractic manipulative therapy procedures than to motor vehicle collision related injuries, even though the comparative biomechanical evidence makes such causation unlikely. The direct evidence suggests that the healthy vertebral artery is not at risk from properly performed chiropractic manipulative procedures.

Defining the effect of cervical manipulation on vertebral artery integrity: establishment of an animal model.

BACKGROUND: Cervical spine manipulation is most often performed to affect relief of musculoskeletal complaints of the head and neck. Performed typically without complication, this modality is thought to be a potential cause of cerebrovascular injury, although a cause-effect relation has yet to be established. To explore this relation, an experimental platform is needed that is accessible and biologically responsive. OBJECTIVE: To establish an animal model capable of accommodating (1) direct study of its vertebral arteries and (2) creation of controlled interventions simulating arterial injury. STUDY DESIGN: Descriptive. METHODS: Under fluoroscopic guidance, an ultrasonic catheter was inserted into the left vertebral artery of 3 anesthetized dogs. The ultrasonic probe was then drawn proximally through the artery at a specific rate, and cross-sectional images of the vessel were collected. These images were then reconstructed to provide a variety of 2- and 3-dimensional representations of the vessel. This procedure was repeated after the overinflation and/or displacement of an angiographic balloon within the vertebral artery itself. RESULTS: The resulting ultrasonic images were able to delineate the structural layers that constitute the vertebral artery. Analysis of 2- and 3-dimensional reconstructions before and after angiographic intervention revealed the creation of discrete vascular injuries (aneurysm or dissection). CONCLUSIONS: For the first time, an animal model has been established that permits direct interrogation of the internal structures of the vertebral artery. This model can also be manipulated to create "preexisting" vascular injuries that are thought to be possible prerequisites for cerebrovascular injury associated with manipulation. As a result, an experimental platform has been established that is capable of providing investigators of all backgrounds with the ability to quantify biologic and mechanical outcomes of cervical manipulation.

[Wallenberg's syndrome secondary to dissection of the vertebral artery caused by chiropractic manipulation]. / Sindrome de Wallemberg secundario a disección de la arteria vertebral por manipulación quiropráctica.

INTRODUCTION: Chiropractic manipulations of the cervical region are techniques that are used more and more frequently to treat a number of osteomuscular pathologies, but can give rise to important complications, such as the dissection of the cervical arteries. Dissection of the vertebral artery generally presents as alternating syndromes, of which Wallenberg s syndrome, either complete or incomplete, is the most frequent. In this paper we review the literature published to date on the pathogenesis, risk factors, clinical features, chronopathology, diagnosis, treatment and prognosis of this complication. CASE REPORT: We describe the case of a young patient who suffered from incomplete Wallenberg s syndrome a few hours after a single session of cervical chiropractic manipulation, and we also show the resonance images that were used to support the diagnosis. CONCLUSIONS: The appearance of a pain in the neck and neurological symptoms in a patient who has undergone chiropractic manipulation in the last few hours or days must lead us to consider a possible dissection of the cervical arteries. Dissection of the vertebral artery usually gives rise to alternating syndromes, the most frequent of which is lateral bulbomedullary infarction or Wallenberg s syndrome due to proximal occlusion of the posteroinferior cerebellar artery. Magnetic resonance angiography of the supra aortic trunks and cranial magnetic resonance scanning are valid techniques for demonstrating the dissection of the artery and the associated ischemic lesion.