Comparison of accuracy in C1-C2 pedicle screw placement: O-arm, 3D guides, and C-arm fluoroscopy.

To evaluate the accuracy and safety of C1-C2 pedicle screw placement using O-arm navigation, individualized 3D-printed guides, and C-arm fluoroscopy. Clinical data of 47 patients who underwent C1-C2 spinal fixation surgery at our institution between January 2015 and December 2020 were retrospectively analyzed. The cohort included 28 males and 19 females, aged 15-59 years (mean age: 46.23 ± 9.97 years). Patients were categorized into three groups based on the screw placement technique: navigation group (11 cases; O-arm S8 navigation system), guide group (15 cases; individualized 3D-printed guides), and fluoroscopy group (21 cases; C-arm fluoroscopy guided by anatomical landmarks). Outcome measures included surgical time, screw placement time, intraoperative blood loss, single-pass screw placement success rate, screw placement accuracy, and complication rate. Surgical Metrics: The Navigation group demonstrated a mean surgical time of 120.72 ± 11.14 min, screw placement time of 20.00 ± 1.09 min, and blood loss of 225.81 ± 25.58 ml. The Guide group reported significantly shorter surgical time (97.46 ± 9.03 min, P < 0.001), shorter screw placement time (15.80 ± 1.93 min, P < 0.001), and reduced blood loss (162.66 ± 18.52 ml, P < 0.001). The Fluoroscopy group showed longer surgical time (121.04 ± 12.81 min) and higher blood loss (239.04 ± 24.54 ml) compared to the other groups. Screw Placement Success and Accuracy: A total of 188 screws were placed (44 in the Navigation group, 60; guide group, and 84; Fluoroscopy group). The single-pass success rates were 100% (44/44) in the navigation group, 93.3% (56/60) in the guide group, and 80.9% (68/84) in the fluoroscopy group (P = 0.002). Screw placement accuracy was 100% (44/44) in the navigation group, 98.3% (59/60) in the guide group, and 85.7% (72/84) in the fluoroscopy group (P = 0.039). Notably, three screws in the fluoroscopy group breached the vertebral artery foramen; however, no cerebrovascular ischemic events were observed. Complications: Two patients in the fluoroscopy group developed postoperative occipitocervical pain owing to intraoperative irritation of the C2 nerve root. Symptoms resolved after corticosteroid and diuretic therapy. No occipitocervical pain or other complications were reported in the Navigation or Guide group. All the incisions healed without infection or delayed recovery. O-arm S8 navigation system and individualized guide plate assisted atlantoaxial screw placement can achieve high and stable accuracy, which is better than the traditional freehand screw placement technique under fluoroscopy; O-arm navigation technology has an advantage in the one-time success rate of atlantoaxial screw placement, which is higher than that of the guide plate group and the fluoroscopy group; Individualized guide plate combined with lateral fluoroscopy can accurately place atlantoaxial screws, save operation time and reduce bleeding.