This case illustrates multilevel cervical spine fractures with involvement of the right foramen transversarium and subsequent vertebral artery thrombosis probably due a traumatic vertebral artery dissection.
The significant force of the trauma has also resulted in multilevel cervical spine interspinous ligament strain. The mechanism of injury is hyperextension, increased rotation with lateral flexion or translation of the cervical spine.
In the scope of trauma, vertebral artery dissections occur due to rapid acceleration–deceleration injury causing rotation and hyperextension of the neck. This occurs simultaneously with lateral bending and axial compression during rollover motor vehicle crashes.
The course of the vertebral artery can be divided into four parts, V1-V4. The first segment, V1, also referred to as the extra-osseous segment, extends from the origin at the subclavian artery to the transverse foramen of the sixth cervical vertebra, C6. However, there are anatomical variations of its entry into C5 and C7. The foraminal or second segment, V2, describes its course in the foramen transversarium ascending cranially from C6 to C1. The third segment, the extraspinal segment, V3, starts as the vertebral artery exits the foramen transversarium of C1, and courses posteromedially along the upper surface of the posterior ring of the atlas. The artery then abruptly turns ventral and cephalic to enter the foramen magnum where it pierces the dura mater. The fourth segment, V4, is referred to as the intradural segment. It extends from dural penetration to the pontomedullary junction where the two vertebral arteries unite in the midline to form the basilar artery.
The second and third parts of the vertebral artery are most susceptible to injury during cervical spine trauma, due to their close proximity to osseous structures. During rotation with hyperextension, lateral translation and flexion distraction injuries of the spine (as can occur during vehicular rollover accidents) there is resultant stenosis or occlusion of one or both vessels. The resulting vascular traumatic lesion can manifest as a dissection, thrombosis, intimal tears, rupture, and/or arteriovenous fistulae.
The treatment options, depending on the resulting type of vascular injury, include conservative management/observation, anticoagulation therapies and/or surgery though primary surgical repair, tamponade, embolization and/or endoluminal therapeutic interventions.
Case courtesy of Associate Professor Pramit Phal