Okada Yuya, Nakashima Hiroaki, Ito Sadayuki, Segi Naoki, Ouchida Jun, Urasaki Tetsuya, Imagama Shiro
Department of Orthopedic Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan.
Department of Orthopedic Surgery, Chutoen General Medical Center, Kakegawa, Japan.
Spine Surg Relat Res. 2024 Dec 20;9(3):313-320. doi: 10.22603/ssrr.2024-0243. eCollection 2025 May 27.
Cervical pedicle screw (CPS) placement is crucial for posterior cervical fusion surgery due to its strong fixation ability. However, CPS insertion is associated with risks, including screw perforation, which can lead to complications such as vertebral artery injury and neurological deficits. Although previous studies have explored some morphological factors affecting CPS placement, comprehensive data on specific parameters contributing to perforation remains limited. This study aimed to investigate cervical vertebrae features associated with CPS perforation and established threshold values for improved preoperative planning.
A retrospective analysis of 36 patients who underwent posterior cervical fusion surgery with CPS placement was conducted using preoperative computed tomography (CT)-based navigation. Cases with CPS insertion at C1 or C2 were excluded. The key morphological parameters-optimal screw trajectory angle, pedicle diameter, and distance from the entry point to the pedicle isthmus (DEP)-were measured on preoperative CT images. CPS placement accuracy was assessed postoperatively using Neo's classification. The receiver operating characteristic (ROC) curve analysis determined the cutoff values for predicting CPS perforation.
Among the 102 CPSs placed from C3 to C7, the overall perforation rate was 25.5%. C3 had the highest perforation rate (45.5%), whereas C7 had the lowest (3.1%). The vertebrae with CPS perforation exhibited a significantly larger optimal screw trajectory angle (45.5° vs. 38.0°, p<0.001), smaller pedicle diameter (4.2 mm vs. 5.2 mm, p<0.001), and longer DEP (13.2 mm vs. 11.9 mm, p=0.002). The ROC analysis identified the following cutoff values: 44.0° for the optimal angle, 4.35 mm for the pedicle diameter, and 12.7 mm for the DEP. These morphological parameters strongly predicted the risk of CPS perforation.
Establishing key morphological thresholds enhances preoperative planning for CPS placement, improves accuracy and patient safety, and minimizes complications.
由于颈椎椎弓根螺钉（CPS）具有强大的固定能力，其置入对于颈椎后路融合手术至关重要。然而，CPS置入存在风险，包括螺钉穿孔，这可能导致椎动脉损伤和神经功能缺损等并发症。尽管先前的研究已经探讨了一些影响CPS置入的形态学因素，但关于导致穿孔的具体参数的全面数据仍然有限。本研究旨在调查与CPS穿孔相关的颈椎特征，并建立阈值以改进术前规划。
对36例行基于术前计算机断层扫描（CT）导航的CPS置入颈椎后路融合手术的患者进行回顾性分析。排除在C1或C2置入CPS的病例。在术前CT图像上测量关键形态学参数——最佳螺钉轨迹角度、椎弓根直径以及从进针点到椎弓根峡部的距离（DEP）。术后使用尼奥分类法评估CPS置入的准确性。采用受试者操作特征（ROC）曲线分析确定预测CPS穿孔的临界值。
在C3至C7置入的102枚CPS中，总体穿孔率为25.5%。C3的穿孔率最高（45.5%），而C7的穿孔率最低（3.1%）。发生CPS穿孔的椎体表现出明显更大的最佳螺钉轨迹角度（45.5°对38.0°，p<0.001）、更小的椎弓根直径（4.2mm对5.2mm，p<0.001）以及更长的DEP（13.2mm对11.9mm，p=0.002）。ROC分析确定了以下临界值：最佳角度为44.0°，椎弓根直径为4.35mm，DEP为12.7mm。这些形态学参数强烈预测了CPS穿孔的风险。
建立关键形态学阈值可加强CPS置入的术前规划，提高准确性和患者安全性，并将并发症降至最低。
