Vertebral artery injury during cervical spine surgery - A survey of more than 5600 operations

Study Design. Retrospective survey. Objective. To clarify the present incidence and management of iatrogenic vertebral artery injury (VAI) during cervical spine surgery. Summary of Background Data. VAI is a rare complication of cervical spine surgery, but it may be catastrophic. Anterior cervical decompression (ACD) and posterior atlantoaxial transarticular screw fixation (Magerl fixation) have been the main causes, with reported incidences of 0.3% to 0.5% and 0% to 8.2%, respectively. Popular new surgical techniques, such as cervical pedicle screw or C1 lateral mass screw fixation, also entail the potential risk of VAI. Methods. A questionnaire was sent to our affiliated hospitals requesting information regarding iatrogenic VAI during cervical spine surgery. Results. Seven spine surgeon groups and 25 general orthopedist groups responded to the questionnaire, with a response rate of 89%. The overall incidence of VAI was 0.14% (8 cases among 5641 cervical spine surgeries). The incidence in anterior cervical decompression procedures was 0.18% and that in Magerl fixation was 1.3%. Inexperienced surgeons tended to commit VAI more frequently. One case of VAI during C1 lateral mass screw fixation was included, whereas there was no case of VAI caused by cervical pedicle screw fixation. In the case of VAI in the screw hole, hemostasis was obtained by tamponade or screw insertion, whereas VAI in the open space sometimes caused uncontrollable bleeding, in which embolization eventually stopped the bleeding. There were no deaths or apparent neurologic sequelae. Conclusion. The incidence of VAI during cervical spine surgery from this survey was similar to or slightly less than that in the literature. Tamponade was effective in many cases, but prompt consultation with an endovascular team is recommended if the bleeding is uncontrollable. Preoperative careful evaluation of the vertebral artery seems to be most important to prevent iatrogenic VAI and to avoid postoperative neurologic sequelae.