VERTEBRAL ARTERY INJURY IN C1-2 TRANSARTICULAR SCREW FIXATION - RESULTS OF A SURVEY OF THE AANS CNS SECTION ON DISORDERS OF THE SPINE AND PERIPHERAL-NERVES/

Object. The 847 active members of the American Association of Neurolog ical Surgeons/Congress of Neurological Surgeons (AANS/CNS) Section on Disorders of the Spine and Peripheral Nerves were surveyed to quantita te the risk of vertebral artery (VA) injury during C1-2 transarticular screw placement. Methods. This retrospective study elicited the numbe r of patients treated with transarticular screws, the number of screws placed, the incidence of VA injury and subsequent neurological defici t, and the management of known or suspected VA injury. Two hundred thi rteen (25.1%) of the 847 surgeons responded. One hundred one responden ts (47.4%) had placed a total of 2492 C1-2 transarticular screws in 13 18 patients. Thirty-one patients (2.4%) had known VA injuries and an a dditional 23 patients (1.7%) were suspected of having injuries. Howeve r, only two (3.7%) of the 54 patients with known or suspected VA injur ies exhibited subsequent neurological deficits and only one (1.9%) die d of bilateral VA injury. Other iatrogenic complications included dura l tears, screw fractures, screw breakout, fusion failure, infection, a nd suboccipital numbness. Conclusions. Including both known and suspec ted cases, the risk of VA injury was 4.1% per patient or 2.2% per scre w inserted. The risk of neurological deficit from VA injury was 0.2% p er patient or 0.1% per screw, and the mortality rate was 0.1%. The cho ice of management of intraoperative VA injuries was evenly divided bet ween placing the patient under observation and initiating immediate po stoperative angiography with possible balloon occlusion.