Introduction: A number of imaging techniques have been introduced to minimize the risk of pedicle screw placement. Intraoperative CT has been recently introduced to assist in spinal instrumentation. In this study, we examine the effectiveness of intraoperative CT in enhancing the safety and accuracy of pedicle screw placement.
Methods: We included all cases from December 2009 to July 2012 in which an intraoperative CT scan was used to confirm pedicle screw placement.
Results: A total of 203 patients met our inclusion criteria. Out of 1148 screws, 103 (8.97%) screws were revised intraoperatively in 72 (35.5%) patients: 14 (18.42%) were revised in the cervical spine (C2 or C7), 25 (7.25%) in the thoracic spine, and 64 (8.80%) in the lumbar spine. Compared to screws in the thoracic and lumbar regions, pedicle screws placed in the cervical region were statistically more likely to be revised (p=0.0061). Two (0.99%) patients required re-operations due to undetected misplacement of pedicle screws.
Conclusions: We describe one of the first North American experiences with the intraoperative CT used to confirm the placement of pedicle screws. Compared to a similar cohort of patients from our institution that had pedicle screws inserted via the free-hand technique with post-operative CT, we found that the intraoperative CT lowers the threshold for pedicle screw revision, resulting in a statistically higher rate of screw revision in the thoracic and lumbar spine (p<0.0001). During our 2.5-year experience with the intraoperative CT, we did not find a reduction in rates of reoperation for misplaced pedicle screws.
Patient Care: This study focuses on the role of the intra-operative CT in pedicle screw placement. The intra-operative CT has been advocated to be a device that contributes to patient safety. Our study provides surgical outcomes relating to this important tool
Learning Objectives: By the conclusion of this session, participants should be able to: 1) Discuss the role and effectiveness of the intra-operative CT; 2) Identify several modalities related to the safety of pedicle screw placement.
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