Vertigo is a sensation of spinning or whirling, where the world feels like it is moving when it is not. A common concern for people considering cervical (neck) manipulation is whether a chiropractic adjustment can cause this unsettling feeling. This article explores the relationship between spinal adjustments and the onset of dizziness or vertigo, detailing the underlying mechanisms and necessary safety measures.
The Direct Answer and Associated Conditions
It is possible for a chiropractic adjustment, particularly one involving the cervical spine, to precede an episode of vertigo, though such occurrences are uncommon. The manipulation can act as a mechanical trigger for pre-existing conditions affecting the balance system, most frequently those related to the inner ear.
This mechanism often involves Benign Paroxysmal Positional Vertigo (BPPV). In BPPV, tiny calcium carbonate crystals (otoliths) become dislodged from the utricle and migrate into the semicircular canals. A rapid head movement, such as during a cervical adjustment, can mechanically shift these crystals. This sends abnormal signals to the brain, resulting in brief, intense spinning vertigo. While the adjustment does not cause the underlying BPPV, it can precipitate the symptoms.
A far more serious, though exceedingly rare, association involves the vascular system and the vertebral artery. A forceful neck rotation could cause a Vertebral Artery Dissection (VAD)—a tear in the artery wall—in an individual with pre-existing vascular weakness. This dissection can lead to a stroke or Vertebrobasilar Insufficiency (VBI), compromising blood flow to the brainstem. The risk of a serious vascular event following a cervical adjustment is extremely low, estimated between 1 in 1 million and 1 in 5.8 million adjustments. Vertigo resulting from this vascular event is a sign of central nervous system involvement and is often accompanied by other specific neurological symptoms.
Understanding Vertigo Originating in the Neck
A less severe form of post-adjustment dizziness is often attributed to Cervicogenic Vertigo (CGV), meaning the symptoms originate from the neck itself. This condition is distinct from inner ear issues like BPPV and vascular problems. CGV arises from a temporary disruption of proprioceptive signals, which are the sensory inputs from the joints and muscles of the upper cervical spine (C1-C3).
The neck muscles and joints contain receptors that inform the brain about the head’s position in space. An adjustment can temporarily alter the communication pathway between the neck and the brain’s balance centers, including the vestibular system. When the brain receives conflicting positional information from the neck, eyes, and inner ear, the result is a sensation of unsteadiness or lightheadedness.
CGV symptoms typically manifest as imbalance, unsteadiness, or general lightheadedness, rather than the true rotational spinning experienced with BPPV. This dizziness is often accompanied by neck pain, stiffness, or a headache at the base of the skull. These symptoms are generally mild and transient, usually subsiding on their own within a few hours or, at most, 24 hours, as the nervous system adapts.
Safety Protocols and Risk Mitigation
Chiropractors employ a thorough screening process to identify patients at higher risk of adverse events, including post-adjustment vertigo. A detailed patient history is obtained to check for prior incidents of dizziness, recent head or neck trauma, high blood pressure, or symptoms suggestive of vascular issues. This initial assessment helps determine if a patient has any contraindications to certain types of neck manipulation.
Practitioners may perform specific physical tests to evaluate the vascular integrity of the neck, though the predictive value of these tests is debated. For patients with risk factors or known neck instability, the practitioner can significantly modify the adjustment technique. This modification often involves using low-force methods, such as instrument-assisted adjustments or gentle mobilization, which avoid high-velocity rotation of the cervical spine. These non-rotational techniques aim to achieve the therapeutic benefit of the adjustment while minimizing mechanical stress on vascular structures.
Recognizing Warning Signs and When to Seek Medical Care
For most people, mild lightheadedness or temporary unsteadiness following an adjustment is a benign, self-limiting reaction, likely related to cervicogenic causes. These mild symptoms, which may include slight nausea or temporary neck soreness, should resolve quickly and do not typically require emergency intervention. Patients should inform their practitioner, but these reactions are usually managed with rest and hydration.
Certain neurological signs, however, are associated with the rare, serious event of Vertebrobasilar Insufficiency (VBI) and require immediate medical attention. These severe symptoms are often remembered using the mnemonic “5 Ds and 3 Ns.” The sudden onset of a severe, unfamiliar headache or neck pain, described as the “worst ever,” is also a significant warning sign.
Warning Signs of VBI
- Dizziness
- Diplopia (double vision)
- Dysarthria (slurred speech)
- Dysphagia (difficulty swallowing)
- Drop attacks (sudden collapse without loss of consciousness)
- Nystagmus (involuntary, jerky eye movements)
- Nausea/Vomiting that is sudden and severe
- Numbness, especially on one side of the body or around the mouth