Accuracy Assessment of Planned Versus Actual Trajectories in Robotic-Assisted Spine Surgery Utilizing Perioperative O-Arm CT Scans

Study design A prospective cohort study. Objectives To find the deviations in entry point, axial angulation, and sagittal angulation between the planned trajectories versus the achieved trajectories in Mazor-X robotic spine surgery. Methods This study was conducted from December 2023 to June 2025, including 250 patients undergoing robotic-assisted pedicle screw fixation. Planned and actual screw trajectories were compared using perioperative O-arm CT scans. Results A total of 1170 screws were inserted (96 thoracic, 1074 lumbar). Mean entry deviation was 2.27 ± 1.5 mm, axial angular deviation 3.7° ± 3.7°, and sagittal deviation 3.4° ± 3.2°. A clinically acceptable placement rate of 99.7% was achieved, with only four breaches requiring revision. Operative time and screw insertion time decreased with experience, reflecting a short learning curve. Conclusion Robotic guidance using the Mazor X Stealth Edition (Medtronic, 2018, Memphis, Tennessee) ensures highly accurate and safe pedicle screw placement in spine surgery.