Incidence of vertebral artery thrombosis in cervical spine trauma: correlation with severity of spinal cord injury

Abstract

Background and purpose: The incidence of blunt traumatic vertebral artery dissection/thrombosis varies widely in published trauma series and is associated with spinal trauma. The purpose of this study was to determine the frequency of traumatic vertebral artery thrombosis (VAT) in cervically injured patients by using routine MR angiography (MRA) and MR imaging and identify associations with the severity of neurologic injury.

Methods: A retrospective review of 1283 patients with nonpenetrating cervical spine fractures with or without an associated spinal cord injury (SCI) was performed. Imaging consisted of routine cervical MR imaging and 2D time-of-flight MRA of the neck. The cervical injury level, neurologic level of injury, and American Spinal Injury Association (ASIA) grade were recorded.

Results: In this study, 632 patients met the inclusion criteria, 83 (13%) of whom had VAT on the admission MR imaging/MRA. Fifty-nine percent (49/83) of VAT patients had an associated SCI. VAT was significantly more common in motor-complete patients (ASIA A and B, 20%) than in neurologically intact (ASIA E, 11%) cervical spine-injured patients (P = .019). VAT incidence was not significantly different between motor-incomplete (ASIA C and D, 10%) and neurologically intact (ASIA E, 11%) cervical spine-injured patients (P = .840).

Conclusion: The absence of neurologic symptoms in a patient with cervical spine fracture does not preclude VAT. VAT associated with cervical spinal injury occurs with similar frequency in both neurologically intact (ASIA E) and motor-incomplete patients (ASIA C and D) but is significantly more common in motor-complete SCI (ASIA A and B).

Fig 1.

A 58-year-old man who sustained a unilateral interfacetal dislocation at C5–C6 without SCI. A, Sagittal T2-weighted fast spin-echo (FSE) image (TR/TE/ETL: 2000/80/8) shows an injured disk at C5–C6 with increased signal intensity in the disk and probably avulsion of the anterior longitudinal ligament (dashed arrow). Prevertebral edema (arrowheads) and edema in the posterior paraspinal musculature (white arrows) are present. B, Nonvisualization of the right vertebral artery. MIP image (anterior view) from a 2D time-of-flight acquisition (TR/TE/flip: 40/8.7/30) shows absence of signal intensity in the expected course of the right vertebral artery (dotted line). C, Thrombus in the right foramen transversarium. Axial image from a 3D GRE acquisition (TR/TE/flip: 37/min/15) shows an oval area of low signal intensity in the right foramen transversarium corresponding to thrombus in the right vertebral artery. Note the normal flow-related enhancement in the left foramen transversarium. D, Thombus in the right vertebral artery. Axial FSE image (TR/TE/ETL: 3000/28/4) obtained at a similar level to image in panel C shows a high-signal-intensity thrombus (arrow) in the right foramen transversarium indicative of a thrombosed vertebral artery. Note the normal flow void of the left vertebral artery in the left foramen transversarium.