Basilar artery thrombosis after reduction of cervical spondyloptosis: a cautionary report

Traumatic cervical spondyloptosis is a rare clinical entity typically associated with complete neurological deficit. The inherent mechanics of this fracture-dislocation pattern contorts the vertebral arteries in such a way that it may result in dissection or compromised flow through those vessels. Thus, intimal injury or thrombus from stasis of flow may result. Reduction of the spondyloptosis restores flow to the vertebral arteries, but it also may mobilize thrombus or propagate an intimal dissection within the previously contorted vessel. The authors review their experience in the care of a 43-year-old man who sustained C4-5 spondyloptosis while riding an all-terrain vehicle. On arrival, the patient demonstrated no motor function below C-4 but had sensation to the nipple line (American Spinal Injury Association Spinal Cord Injury Classification B). The patient's cranial nerve examination was unremarkable. Computed tomography of the cervical spine demonstrated complete spondyloptosis at C4-5. The patient was immediately placed in cervical traction and taken to the operating room for open reduction of the fracture dislocation, decompression of the spinal cord, and stabilization with an interbody graft and cervical plate. Preoperative cervical traction was successful in only partial reduction of the fracture dislocation. Open reduction was achieved with exposure of the C-4 and C-5 bodies and sequential distraction. After anatomical alignment was achieved, an interbody graft was placed and a cervical plate secured. A subsequent decline in the patient's level of consciousness prompted CT of the head, which showed evidence of a basilar artery thrombosis. A CT angiographic study demonstrated patency of the vertebral arteries, but a mid-basilar artery thrombosis. The patient progressed to brain death 24 hours after reduction of the fracture dislocation. The degree of contortion of the vertebral arteries in cervical spondyloptosis in the upper cervical spine may result in stasis of flow with subsequent formation of thrombus or intimal injury. After anatomical reduction, restoration of flow within the vertebral arteries may mobilize the thrombus or propagate an intimal dissection and result in subsequent embolic events. Endovascular evaluation may be warranted immediately after anatomical reduction of a high cervical spondyloptosis for evaluation of the vertebral arteries and possible thrombus dissolution or retrieval.