C-arm cone beam computed tomography with needle path overlay during fluoroscopic-guided screw placement for a spinal lesion

Accurate screw placement is essential in spinal surgery. To enhance precision, navigation-guided techniques using fluoroscopy or computed tomography (CT) have been developed. Recently, overlay technology has emerged, enabling real-time projection of preoperative planning onto fluoroscopic images through C-arm–based cone-beam CT (CBCT). Needle-guidance–based overlay technology was applied to the surgical management of odontoid fractures and pedicle screw placement, with accuracy and clinical outcomes systematically evaluated. A retrospective review was performed of three cases in which intraoperative overlay guidance using C-arm CBCT was considered effective for spinal surgery between February and June 2017. Case 1 involved a 26-year-old man with an Anderson type II odontoid fracture. Case 2 involved a 75-year-old woman with atlantoaxial dislocation. Case 3 involved a 66-year-old man with a vertebral arch fracture. For each case, postoperative imaging was used to assess the deviation between the planned trajectory and the actual implant position. In Case 1, the deviation from the planned target point measured 2.57 mm. In Case 2, deviation were 0.71 mm (right C1), 0.98 mm (left C1), 0.35 mm (right C2), and 0.31 mm (left C2), producing a mean deviation of 0.59 mm. In Case 3, deviations were 0.88 mm (right L3), 2.21 mm (left L3), 2.37 mm (right L5), and 1.85 mm (left L5), resulting in a mean deviation of 1.83 mm. No major complications were observed in any of the three cases. Needle-guidance overlay technology extends beyond biopsy to encompass odontoid screw fixation and pedicle screw placement, demonstrating technical feasibility for accurate screw placement. In this study, implementation of the technique appeared to reduce the need for a separate navigation system without adding distinct invasive steps. It was also relatively straightforward to implement, suggesting feasibility even in smaller medical facilities.