Bowhunter’s syndrome (rotational vertebral artery syndrome) is a very rare vascular disorder caused by kinking of the dominant vertebral artery at the atlanto-axial joint during neck turning.
It is similar to what happens when a garden hose is twisted, kinking it and cutting off the flow of water. In this condition, turning the neck “kinks” the main vertebral artery, which carries blood to the brainstem and cerebellum, resulting in ischemia and vertigo. It is named “bowhunter’s syndrome because the neck position that causes the vertigo is the same as the position assumed an archer getting ready to fire an arrow. Returning the neck to the middle position restores the blood supply, and leads to resolution of vertigo.
It typically affects older men, and rarely presents with isolated vertigo, but is usually accompanied by other posterior circulation symptoms (see vertebrobasilar stroke). It is important to distinguish bowhunter’s syndrome from other disorders characterized by head or neck movements triggering vertigo or dizziness, like benign paroxysmal positional vertigo (BPPV), vestibular migraine, and cervicogenic dizziness. The diagnosis is made when impaired blood supply with neck turning is observed with transcranial Doppler ultrasound or dynamic digital subtraction angiography with neck turning.