Dear Editor:
I appreciate the thoughtful letter from Drs. Brown and Chaibi (Dynamic Chiropractic, December 2025) reinforcing the importance of vigilance in recognizing signs of ischemia prior to performing a cervical adjustment. Their emphasis on evidence-based screening frameworks (e.g., Chaibi, et al., 2019) complements my original article's focus on post-adjustment emergency response.
However, as an attorney with extensive experience defending chiropractors in stroke-related litigation, John Salvucci has observed that conflating signs of a vertebral artery dissection (VAD) with signs of an ischemic stroke often underlies unfounded claims. The two are clinically and pathophysiologically distinct, and clarifying this distinction remains essential for both patient safety and fair risk assessment.
Pathophysiology and Diagnostic Challenges: The pathophysiology of vertebral artery dissection is poorly understood.1 Classic symptoms like neck pain and headache are common to many ailments, and there are no reliable clinical tests to confirm VAD prior to manipulation.2 As noted in the 2004 ACC statement, provocative tests like George's Test were discontinued due to high false-positive rates, inability to rule out VAD, and lack of safety validation.2
If valid clinical tests existed, they would be widely adopted by emergency department physicians and neurologists, potentially reducing denials of imaging for patients with dissection but no active stroke.
Distinguishing VAD from Stroke: It is important to recognize that a vertebral artery dissection with thrombus formation is a distinct and separate pathophysiologic process from a thromboembolic ischemic stroke. The latter has recognized clinical signs and symptoms which help differentiate it. It is tempting to conflate the two processes, especially when they are temporally connected.
One result of this common mistaken conflation is the criticism of a chiropractor for failing to recognize and refer for a "dissection in progress." There are signs of a stroke in progress, but not a "dissection in progress," other than neck pain and headache.
What does dissection in progress refer to? Does it refer to the period following a tear of the intima and the formation of the thrombus? Is it limited to those cases in which a tear has occurred and that tear is expanding? If so, what studies have demarcated the clinical changes as that evolution occurs? Debette and Leys (2009) highlight the sparse evidence on cervical artery dissection (CAD) progression, often linked to minor trauma but without clear clinical markers.1
Challenges with Posterior Circulation Strokes (PCS): When ischemic stroke does occur, the “classic” signs (hemiparesis, aphasia, facial droop) overwhelmingly reflect anterior circulation events. The signs of a PCS are far more variable and difficult to recognize.3-4 In one study conducted at certified stroke centers, emergency medicine physicians and neurologists initially missed 37% of posterior circulation strokes versus only 16% of anterior strokes (p < 0.001), largely because of atypical symptoms such as dizziness, nausea, and vomiting.3
Hoyer and Szabo note that the signs of a PCS frequently mimic benign conditions and escape detection even with standardized triage systems.4
Missing the signs of an ischemic stroke in progress may be a valid criticism; however, accusing a chiropractor of missing the signs and symptoms of a VAD when common symptoms such as neck pain and headache are charted is mistaken. We appreciate Brown and Chaibi’s call for structured risk-benefit assessment before an adjustment, while recognizing that current clinical tools to do such assessment have well-documented limitations.
References
- Debette S, Leys D. Cervical-artery dissections: predisposing factors, diagnosis, and outcome. Lancet Neurol, 2009;8(7):668-678.
- Association of Chiropractic Colleges - position on George's Test, 2004. Referenced in: “How Chiropractic Research Impacts All DCs.” NCMIC, March 10, 2021. Read Here
- Arch AE, Weisman DC, Coca S, et al. Missed ischemic stroke diagnosis in the emergency department by emergency medicine and neurology services. Stroke, 2016;47(3):668-673.
- Hoyer C, Szabo K. Pitfalls in the diagnosis of posterior circulation stroke in the emergency setting. Front Neurol, 2021;12:682827.
Brandon Hoffman, BA
Scottsdale, Ariz.
John Salvucci, Esq.
Philadelphia, Pa.
