Computed tomography-based navigation-assisted pedicle screw insertion for thoracic and lumbar spine fractures.

BACKGROUND Incorrect placement of pedicle screws may lead to neurovascular injury, so the position is important for the reduction of spinal fractures. CT-based image-guided surgery has been promoted as a means to theoretically improve the accuracy of pedicle screw placement. Patients who underwent CT-based navigation-assisted pedicle screw fixation for thoracic or lumbar fractures were reviewed to evaluate the accuracy of pedicle screw placement for spinal fracture cases. METHODS A computed tomographic (CT)-based image-guided system (BrainLAB) was used for pedicle screw insertion in 14 patients with thoracic or lumbar spine fractures. The accuracy of pedicle screw placement was analyzed by the preoperative and postoperative Cobb's angle and sagittal screw angle with a review of radiographic images, and the penetration of the pedicle cortex by postoperative CT scans. RESULTS Under the guidance of CT-based navigation 102 screws were inserted. Cobb's angle was corrected to an average of 15 degrees in the 14 patients. The sagittal screw angle was less than 10 degrees for 92 (90.2 %) screws, and the overall average was 5 degrees. The results of the postoperative CT review showed only 3 (2.9 %) screws penetrated the pedicle cortex laterally and no screw penetrated medially. No iagtrogenic neurological injury was found. CONCLUSION The accuracy of pedicle screw placement is crucial for thoracolumbar spine fracture fixation. The placement of pedicle screws can be done accurately with the aid of a CT-based image-guided system. Furthermore, this opens the possibility for surgeons to reduce radiation exposure by eliminating the need for intraoperative fluoroscopy.