[Neck-induced vertigo].

Cervicogenic vertigo can be elicited by hyperactivity of spinovestibular afferents and, much more seldomly, by episodic reduction of blood flow in the vertebral artery. The afferent hyperactivity to the vestibular system derives from a "circulus vitiosus" involving false posture, pain, joint dysfunction, which in turn exacerbates the false posture - and so on. This is to be observed in the joints CO/C1 and C1/C2 and their short muscles. This dysfunction of the upper cervical spine can be determined by exact anamnesis, careful investigation of neck mobility, joint play and muscle tension. The cervical nystagmus observed during the neck torsion test is short (seconds) in functional diseases (hyperactivity) and longlasting (minutes) in cases of vascular disorder. Cervical vertigo should be differentiated from other atactic disorders, especially those arising from benign paroxysmal positional vertigo and from Menière's disease.