Spontaneous atraumatic vertebral artery occlusion due to physiological cervical extension

Abstract

Vertebral artery (VA) occlusion is a serious and potentially life-threatening occurrence. Bow hunter's syndrome, a mechanical occlusion of the VA due to physiological head rotation, has been well described in the medical literature. However, mechanical VA compression due to routine flexion or extension of the neck has not been previously reported. The authors present the unique case of a woman without any history of trauma who had multiple posterior fossa strokes and was found to have dynamic occlusion of her right VA visualized via cerebral angiogram upon extension of her neck. This occlusion was attributed to instability at the occipitocervical junction in a patient with a previously unknown congenital fusion of both the occiput to C-1 and C-2 to C-3. An occiput to C-3 fusion was performed to stabilize her cervical spine and minimize the dynamic vascular compression. A postoperative angiogram showed no evidence of restricted flow with flexion or extension of the neck. This case emphasizes the importance of considering symptoms of vertebrobasilar insufficiency as a result of physiological head movement. The authors also review the literature on VA compression resulting from physiological head movement as well as strategies for clinical diagnosis and treatment.

A young woman with traumatic vertebral artery occlusion: a case report

“… 2 Bow Hunter’s syndrome is a mechanical occlusion of the VA due to physiological head rotation. 3 Vertebral artery injury (VAI), may result from penetrating injuries, chiropractic manipulation, prolonged abnormal positioning of the neck, birth trauma or from closed head or neck trauma. Nevertheless, damage to the artery as a result of closed injury is considered to be rare.…”

Changes in Vertebral Artery Hemodynamics Associated With McKenzie Therapeutic Cervical Movements: An Exploration Using Duplex Ultrasound Imaging

“…It is possible that this is why the McKenzie cervical approach has been shown to be successful in managing mechanically induced pain and related symptoms. 28,29 The current study suggests that the McKenzie cervical approach could address conditions related to VA insufficiency. However, this is only a hypothesis because the current study only measured healthy participants.…”

“…For example, neck rotation, extension, and loss of cervical lordosis can cause luminal narrowing and reduce the VA blood flow, which might lead to a mechanical occlusion to the VA. It has been suggested that 29,30 neck rotation can compress to the VA through the dynamic stretching to the facet that can stretch the VA, where axial rotation of the cervical spine places the VA under high strain force. 31 In contrast, another study found minimal effects from head and neck positions on the VA blood flow.…”

Bow hunter’s syndrome due to an embolic mechanism: illustrative case

“…There were 22 patients with BHS due to embolic mechanisms, including the present case, as shown in Table 1. 3,[5][6][7][8][9][10][11][12][13][14][15][16][17][18] The overall mean age of the patients was 31 ± 22 years (Table 2). BHS due to an embolic mechanism was observed in 20 men and 2 women.…”