Steven Brown, DC, CICE, Dipl Ac

When presented with a case of cervical artery stroke allegedly associated with Chiropractic cervical spine manipulation, malpractice attorneys often want to argue direct causation. Research studies have found that a direct cause and effect relationship between cervical spine manipulation and cervical artery stroke is not established. Malpractice attorneys should instead consider arguing the Doctor of Chiropractic’s failure to diagnose an ongoing cervical artery dissection event and refer the patient for emergency medical care.

Mechanism of Cervical Artery Stroke

A tear in the inner lining of a cervical artery is referred to as a “dissection”. A dissection may be spontaneous or caused by trauma. A blood clot formed over the area of dissection may subsequently be dislodged and block a smaller artery that supplies the brain, causing a stroke. Alternatively, the blood clot may not dislodge, but may become so large it blocks the cervical artery itself, causing a stroke. The cervical arteries under consideration in this article are the vertebral artery and the carotid artery.

Direct Cause & Effect Relationship

The type of trauma that has been associated with cervical artery dissection is significant trauma such as motor vehicle accidents and the athletic injuries. A direct cause and effect relationship between cervical spine manipulation and cervical artery dissection/stroke is not supported by research. For example:

“VBA (vertebrobasilar artery) stroke is a very rare event in the population. The increased risks of VBA stroke associated with Chiropractic and PCP visits is likely due to patients with headache and neck pain from VBA dissection seeking care before their stroke. We found no evidence of excess risk of VBA stroke associated Chiropractic care compared to primary care.”1 

“We found no excess risk of carotid artery stroke after Chiropractic care. Associations between Chiropractic and PCP visits and stroke were similar and likely due to patients with early dissection-related symptoms seeking care prior to developing their strokes.”2 

“The medical literature does not support a clear causal relationship between CMT (Chiropractic Manipulative Therapy) and ICAD (Internal Carotid Artery Dissection). Reported cases are exceedingly scarce, and none support clear cause and effect.”3

Failure to Diagnose & Refer

Even though it is not possible to prove direction causation in these cases, failure to diagnose and refer may be present on the part of the Doctor of Chiropractic. Cervical arterial dissection causes neck pain which feels the same as neck pain caused by musculoskeletal conditions. Therefore, many patients seek Chiropractic care for what they assume is musculoskeletal condition in their neck.

The Doctor of Chiropractic is under a duty to accurately diagnose the patient and make the appropriate referral, if necessary. A common scenario is that the Doctor of Chiropractic initially fails to diagnose the condition properly and performs cervical spine manipulation on a patient with an ongoing arterial dissection. In most cases of cervical spine manipulation being done in the presence of a cervical arterial dissection, manipulation is uncomfortable and ineffective, but there is not an immediate stroke event following manipulation. For this reason, it is imperative that the Doctor of Chiropractic re-evaluate treatment on each visit.

If cervical spine manipulation is uncomfortable and symptoms do not show improvement within 72 hours of an initial treatment, the Doctor should re-evaluate his diagnosis and consider that the patient’s neck pain may not be musculoskeletal in nature. They should then perform further evaluation and refer the patient for emergency medical care if they suspect cervical artery dissection. If they do not do so, they have breached the standard of care for the Chiropractic profession and are guilty of failure to diagnose and refer.

Objection to Duty to Diagnose 1

Opposing counsel may argue that diagnosis of cervical artery dissection is outside the scope of practice of a Doctor of Chiropractic. This varies from state to state, so an attorney should always review the scope of practice for Chiropractic in the involved state. Here are a few examples with emphasis added:

Arizona Chiropractic Scope of Practice

Arizona has a neuromusculoskeletal scope of practice. Cervical artery dissection and stroke are neurological disorders and would fall underneath this neuromusculoskeletal scope of practice. Arizona Revised Statues 32-925 defines Chiropractic scope of practice as follows: 

Practice of Chiropractic; limitations A. A Doctor of Chiropractic is a portal of entry health care provider who engages in the practice of health care that includes: 1. The diagnosis and correction of subluxations, functional vertebral or articular dysarthrosis or neuromuscular skeletal disorders for the restoration and maintenance of health. 

Oregon Chiropractic Scope of Practice

Oregon also has neuromusculoskeletal scope of practice. Oregon Revised Statutes 684.010 defines Chiropractic scope of practice as follows:

(2) “Chiropractic” is defined as: (b) The chiropractic diagnosis, treatment and prevention of body dysfunction; correction, maintenance of the structural and functional integrity of the neuro-musculoskeletal system and the effects thereof or interferences therewith by the utilization of all recognized and accepted chiropractic diagnostic procedures and the employment of all rational therapeutic measures as taught in approved chiropractic colleges. 

Texas Chiropractic Scope of Practice

Texas limits Chiropractic scope of practice to musculoskeletal disorders. In this case, the Doctor of Chiropractic may not be under a duty to diagnose a neurological condition (however, they may still be under a duty to refer). Texas Occupations Code 3C defines Chiropractic scope of practice as follows:

Sec. 201.002.  PRACTICE OF CHIROPRACTIC. (b)  A person practices chiropractic under this chapter if the person: (1) uses objective or subjective means to diagnose, analyze, examine, or evaluate the biomechanical condition of the spine and musculoskeletal system of the human body;

The Texas Medical Association (TMA) has written an official letter on this subject to the Texas Board of Chiropractic Examiners (TBCE). The letter was written in the context of Doctors of Chiropractic attempting to get the right to practice Acupuncture in the State of Texas. The TMA expressed the following opinion: “The Chiropractic Act restricts the practice of chiropractic to analyzing, examining or evaluating the biomechanical condition of the spine or musculoskeletal system, and to performing certain procedures to improve the subluxation complex or the biomechanics of the musculoskeletal system. Nothing in the Chiropractic Act authorizes a chiropractor to analyze or stimulate the nervous system or to perform acupuncture.”4

Utah Chiropractic Scope of Practice

The Utah Chiropractic Physician Act Part 1 58-73-102 defines Chiropractic scope of practice very broadly:

(9) “Practice of chiropractic” means a practice of a branch of the healing arts: (c) that involves examining, diagnosing, treating, correcting, or prescribing treatment for any human disease ailment, injury, infirmity, deformity, pain, or other condition, or the attempt to do so, in accordance with Section 58-73-601;

Objection to Duty to Diagnose 2

Opposing counsel may argue that Doctors of Chiropractic are not trained to diagnose a cervical artery dissection. This is not the case. DC’s are trained in the orthopedic and neurological examination procedures necessary to make the diagnosis. If imaging is needed to confirm the diagnosis, magnetic resonance angiography (MRA) or computer tomography angiography (CTA) are the imaging studies of choice. Doctors of Chiropractic can order MRA and CTA examinations in states with a neuromusculoskeletal scope of practice.

However, while the diagnosis of a cervical artery dissection may be within the scope of practice of a Doctor of Chiropractic, treatment of a cervical artery dissection is outside their scope of practice, and a stroke can occur at any time when an ongoing cervical artery dissection is present. A stroke could occur in the time it takes for a Doctor of Chiropractic to order MRA or CTA imaging. Instead, immediate referral to the ER is indicated, where the patient can receive imaging to confirm the diagnosis and emergency treatment which can prevent a stroke from occurring.

Case Study 1

This case involves a 50 year old male in Utah who consulted with a Doctor of Chiropractic complaining of vertigo and balance trouble. He received cervical spine manipulation on that visit with no complications, but also with no relief of vertigo and balance trouble. The DC recommended the patient see their primary care physician for further evaluation.

The patient saw the Physician Assistant (PA) at his primary care office three days later. The PA felt the patient might be having some sinus trouble causing his dizziness and recommended a Flonase trial. The trial of Flonase did not provide any relief of vertigo and balance trouble.

The patient consulted with a different Doctor of Chiropractic 11 days later, with continued complaints of dizziness and balance trouble. Two days prior, the patient had a severe episode of cold sweats, weakness and dizziness. The Doctor of Chiropractic performed a cervical spine manipulation. The patient again had no complications following the cervical spine manipulation, but again no relief of any symptoms.

The following morning, the patient experienced severe dizziness and lost consciousness. The patient was taken to a hospital where CTA imaging showed vertebral artery dissection and occlusion in the V3 and V4 segments of the left vertebral artery. The patient was diagnosed with a left cerebellar stroke with resultant quadriplegia and other related damages.

Although it is not possible to prove a direct cause and effect relationship between cervical spine manipulation and the stroke, failure to diagnose and refer is present. The patient was experiencing symptoms of an ongoing vertebral artery dissection event prior to cervical spine manipulation. All three providers, two DC’s and the PA, failed to diagnose the patient with an ongoing vertebral artery dissection event and refer the patient for emergency medical care. But for the failure of these providers to properly diagnose and refer, the stroke and resultant quadriplegia would not have occurred. All three providers were named in the lawsuit. This case is in litigation.

Case Study 2

A 33 year old male in Oregon received eight cervical spine manipulations from a Doctor of Chiropractic. The patient stated that his last cervical spine manipulation was painful and caused moderate pain in the right side of the neck which became constant. 24 days after the last cervical spine manipulation the patient began to experience vision difficulties, and then two days later suffered a right carotid artery stroke.

The patient claimed they had no neck complaints prior to the last cervical spine manipulation, but research into the patient file revealed that on the last five visits the patient complained of mild-moderate dull aching, tightness, and stiffness in his neck. These last five cervical spine manipulations were performed over a period of seven months. The Doctor of Chiropractic failed to diagnose and refer after seven months of neck pain which did not resolve with treatment.

Again in this case, it is not possible to prove direct causation, but failure to diagnose and refer for emergency medical care is present. It is probable this patient had a right carotid artery dissection begin seven months prior to the last cervical spine manipulation. But for the failure of the Doctor of Chiropractic to diagnose and refer, the patient would not have suffered the right carotid artery stroke. This case is in litigation.

Conclusion

Research studies have concluded that a direct cause and effect relationship between cervical spine manipulation and cervical artery stroke is not established. However, Doctors of Chiropractic violate the standard of care by their failure to diagnose an ongoing cervical artery dissection event and refer for emergency medical care. Malpractice attorneys should evaluate for failure to diagnose and refer in any case involving cervical artery stroke and Chiropractic cervical spine manipulation.

About the Author

Steven Brown, DC, CICE, Dipl Ac, is an expert witness specializing in Chiropractic malpractice cases. He is Certified Independent Chiropractic Examiner with the American Board of Independent Medical Examiners, and holds Advanced Certification in Whiplash Biomechanics & Injury Traumatology from the Spine Research Institute of San Diego. Dr. Brown is located in Gilbert, Arizona and can be reached at 480-377-1226 or drbrown@brownchiro.com.

References

  1. Cassidy, et al. Risk of Vertebrobasilar Stroke and Chiropractic Care. SPINE, 2008, Volume 33, Number 34, S176-S183.
  2. Cassidy, et al. Risk of Carotid Stroke after Chiropractic Care: A Population-Based Crossover Study. Journal of Stroke and Cerebrovascular Diseases, 2017 April, Vol 26, No. 4, 842-850.
  3. Haneline, Croft, et al. Association of Internal Carotid Artery Dissection & Chiropractic Manipulation THE NEUROLOGIST 9:35–44, 2003.
  4. Curran, Douglas. Letter to the Texas Board of Chiropractic Examiners from the Texas Medical Association. August 15, 2018.