Comparison of the accuracies of transpedicular screw insertion during computed tomography-free, -based, and intraoperative computed tomography spinal surgeries

Purpose: This study aims to compare the accuracies of transpedicular screw (TPS) insertion using with computed tomography (CT)-free, CT-based, and intraoperative CT (iCT) with integrated navigation during lumbar spinal surgery. Materials and Methods: This study is a retrospective cohort study comparing perioperative data from three patient groups-CT-free navigation (CTF) group, CT-based navigation (CTB) group, andiCT group-who were treated at the Orthopedic Department of Chang Gung Memorial Hospital, Chiayi, Taiwan. Patients who received posterior lumbar TPS insertion with the assistance of computer navigation from January 2002 to June 2011 were included in the study. All demographic and perioperative data were collected from reviews of the medical charts. Postoperative CT images were reviewed to determine screw position. Results: This study enrolled 56 patients: 22 patients were enrolled in the CTF group (106 screws), 15 patients in the CTB group (70 screws), and 19 patients in the iCT group (114 screws). The rate of screw insertion without pedicle wall penetration was 89.62% in the CTF group, 98% in the CTB group, and 98% in the iCT group. (. p = 0.01) The rate of pedicle wall penetration >2 mm was 5.66%, 0%, and 0% in the CTF, CTB, and iCT groups, respectively. One patient in the CTF group developed a residual neurologic deficit. There were noscrew-related complications in the CTB or iCT groups. Conclusion: The use of CT navigation (CT-based and iCT navigations) results in a significantly higher accuracy of screw insertion compared with two-dimensional fluoroscopic navigation for TPS insertion (. p = 0.01). Intraoperative CT-integrated navigation provides additional advantages, including simpler registration and the ability to double-check positioning during the operation, andtends to produce less blood loss.