Abstract: The aim of this study was to assess the potential of surgical guides as a complementary tool to augmented reality (AR) in enhancing the safety and precision of pedicle screw placement in spinal surgery. Four trainers were divided into the AR navigation group using surgical guides and the free-hand group. Each group consisted of a novice and an experienced spine surgeon. A total of 80 pedicle screws were implanted. First, the AR group reconstructed the 3D model and planned the screw insertion route according to the computed tomography data of L2 lumbar vertebrae. Then, the Microsoft HoloLensTM 2 was used to identify the vertebral model, and the planned virtual path was superimposed on the real cone model. Next, the screw was placed according to the projected trajectory. Finally, Micron Tracker was used to measure the deviation of screws from the preoperatively planned trajectory, and pedicle screws were evaluated using the Gertzbein-Robbins scale. In the AR group, the linear deviations of the experienced doctor and the novice were (1.59±0.39) mm and (1.73±0.52) mm respectively, and the angle deviations were 2.72◦ ± 0.61◦ and 2.87◦ ± 0.63◦ respectively. In the free-hand group, the linear deviations of the experienced doctor and the novice were (2.88 ± 0.58) mm and (5.25 ± 0.62) mm respectively, and the angle deviations were 4.41◦ ± 1.18◦ and 7.15◦ ± 1.45◦ respectively. Both kinds of deviations between the two groups were significantly different (P < 0.05). The screw accuracy rate was 95% in the AR navigation group and 77.5% in the free-hand group. The results of this study indicate that the integration of surgical guides and AR is an innovative technique that can substantially enhance the safety and precision of spinal surgery and assist inexperienced doctors in completing the surgery.

Key words: augmented reality (AR), pedicle screw placement, surgery navigation, surgical guide

摘要： 本研究目的是评估手术导板作为增强现实的补充工具在提高脊柱手术中椎弓根螺钉放置的安全性和精度方面的潜力。将4名训练者分为使用手术导板的增强现实导航组和徒手组，每个小组由一名新手和一名经验丰富的脊柱外科医生组成。共植入了80颗椎弓根螺钉。首先，AR组重建三维模型，根据L2腰椎CT数据规划螺钉插入路线;接下来，利用Microsoft HoloLens™ 2识别脊椎模型，将计划的虚拟路径叠加在真实的锥体模型上。接下来，根据投影轨迹放置螺钉。最后，使用Micron Tracker测量螺钉与术前计划轨迹的偏差，并使用Gertzbein-Robbins量表评估椎弓根螺钉。实验结果显示，增强现实导航组有经验的医生和新手训练者的线性偏差分别为(1.59 ± 0.39) mm和(1.73 ± 0.52) mm，角度偏差分别为2.72° ± 0.61°和2.87°± 0.63°。在徒手组中，有经验的医生和新手训练者的线性偏差分别为(2.88 ± 0.58）mm和(5.25 ± 0.62）mm，角度偏差分别为4.41° ± 1.18°和7.15° ± 1.45°。两组间偏差均有统计学意义(P < 0.05)。增强现实导航组的螺钉置入准确率为95%，徒手组的螺钉置入准确率为77.5%。研究结果表明，手术导板与增强现实的结合是一种创新技术，可以显著提高脊柱手术的安全性和精度，并协助没有经验的医生完成手术。

关键词: 增强现实，椎弓根螺钉放置，手术导航，手术导板