Katsumi Shunsuke, Shinohara Akira, Arimura Daigo, Obata Shintaro, Wakiya Hiroki, Saito Mitsuru
Department of Orthopaedic Surgery, Jikei University School of Medicine, Tokyo, Japan.
Eur Spine J. 2025 Aug 26. doi: 10.1007/s00586-025-09210-3.
This study aimed to evaluate the accuracy of pedicle screw placement using intraoperative computed tomography (CT)-based navigation in adolescent idiopathic scoliosis (AIS) surgery and to identify both patient- and screw-level risk factors associated with clinically significant screw deviation.
A total of 1,082 pedicle screws were placed in 67 consecutive AIS patients using intraoperative CT-guided navigation. Screw placement accuracy was graded according to the Gertzbein and Robbins classification system, with Grade C or D (≥ 2-mm cortical breach) defined as clinically significant deviation. Univariate and multivariate logistic regression analyses were performed to investigate risk factors for screw deviation, including morphometric parameters and surgical variables such as the distance from the navigation reference frame (RF).
The overall rate of clinically significant screw deviation was 3.0%. Among patient-level factors, Lenke type 5 curves were associated with a significantly lower risk of deviation compared to type 1 curves (odds ratio [OR] 0.203, P = 0.026). At the screw level, the screw-to-pedicle diameter ratio was the strongest independent predictor of deviation (OR 1.607, P < 0.001). Larger pedicle and screw diameters were associated with lower risk, while increased distance from the RF showed a trend toward higher deviation risk (P = 0.058).
Intraoperative CT-based navigation provides highly accurate pedicle screw placement in AIS surgery. Screw-to-pedicle diameter ratio and RF position represent critical determinants of deviation risk. Tailoring screw selection to pedicle anatomy and optimizing RF placement may improve safety and precision in spinal deformity correction.
本研究旨在评估在青少年特发性脊柱侧凸（AIS）手术中使用术中计算机断层扫描（CT）导航进行椎弓根螺钉置入的准确性，并确定与临床上显著螺钉偏差相关的患者和螺钉水平的危险因素。
连续67例AIS患者共置入1082枚椎弓根螺钉，采用术中CT引导导航。螺钉置入准确性根据Gertzbein和Robbins分类系统分级，C级或D级（皮质骨破裂≥2mm）定义为临床上显著偏差。进行单因素和多因素逻辑回归分析以研究螺钉偏差的危险因素，包括形态学参数和手术变量，如距导航参考框架（RF）的距离。
临床上显著螺钉偏差的总体发生率为3.0%。在患者水平因素中，与1型曲线相比，Lenke 5型曲线的偏差风险显著更低（比值比[OR]0.203，P = 0.026）。在螺钉水平，螺钉与椎弓根直径比是偏差的最强独立预测因素（OR 1.607，P < 0.001）。较大的椎弓根和螺钉直径与较低风险相关，而距RF距离增加显示出偏差风险升高的趋势（P = 0.058）。
术中CT导航在AIS手术中提供了高度准确的椎弓根螺钉置入。螺钉与椎弓根直径比和RF位置是偏差风险的关键决定因素。根据椎弓根解剖结构调整螺钉选择并优化RF放置可能会提高脊柱畸形矫正的安全性和精确性。
