Is Cervical Spine Manipulation All It’s Cracked Up to Be?

When Brit Long brought us another segment, "High Risk, Low Prevalence: Spontaneous Cervical Artery Dissection" in his  High Risk/Low Prevalence series on ERcast, he dove deep into the world of spontaneous arterial dissections, particularly cervical artery dissections (SCAD). While the term “spontaneous” suggests these cases occur without a clear cause, studies show that up to 40% of SCAD cases follow minor trauma—and among the suspected culprits? Cervical spine manipulation therapy (CMT)

Is There a Link Between Chiropractic Manipulation and Cervical Artery Dissection?

Chiropractic literature broadly supports the safety and efficacy of CMT, but data on its risks remain murky.  Some studies suggest a strong association between CMT and cervical artery dissection (CAD), including internal carotid artery dissection and vertebral artery dissection (VAD).

• A 2013 analysis of over 900 cerebral artery dissections linked to CMT found that 700+ cases resulted in stroke-like symptoms (Wynd et al.).
• Plachinski et al. reported that CMT was associated with 4% of all cervical artery dissections and 6% of vertebral artery dissections.

On the other hand, a Canadian Chiropractic Association study estimated SCAD cases occurred at most once per ~8 million office visits, suggesting a lifetime incidence of one case per 48 chiropractors—although the methodology behind these estimates is somewhat questionable. 

So, while the exact incidence of SCAD following CMT is unclear, what remains clear is that chiropractic manipulation is widely used.  ~50% of adults in the U.S. will see a chiropractor at some point in their life.  How should clinicians discuss the potential risk of SCAD with patients considering CMT?

The American Heart Association (AHA) and American Stroke Association (ASA) have weighed in:

• CMT is associated with an increased risk of cervical artery dissection (CAD), particularly vertebral artery dissection (VAD).
• In patients under 45, the incidence of vertebral artery dissection linked to CMT is estimated at 1.3 cases per 100,000 encounters within a week of manipulation.

While there’s no definitive causal link, this data reinforces that patients should be informed of potential risks—especially since the benefits of CMT for cervical pain remain unproven compared to standard therapy.

High Risk, Low Prevalence: Why Clinicians Should Be Cautious

The connection between CMT and SCAD seems real, but the absolute risk is low. Most patients undergo CMT without complications, but when SCAD occurs, the results can be devastating—including carotid artery dissection and stroke. 

Recently, a patient asked me if they should go to see a chiropractor following a low-speed motor vehicle collision. Instead of launching into a soapbox speech, I broke it down like this: 

• There is an association between cervical spine manipulation and artery dissection—though the true incidence is unknown.
• There is no high-quality evidence that CMT outperforms standard therapy for neck pain.
• The chiropractic community argues that their literature is too novel to compare to traditional medical studies—but even in their own research, definitive benefits remain unclear.

Proceed With Caution

While there may be some benefits to chiropractic manipulation involving other aspects of the spine, without clear signal of the benefit outweighing the potential risk I’d strongly recommend that anyone who sees a chiropractor should avoid any cervical spine manipulation.