Study Design: 

A 3D-CT Study.

Objective: 

To research the feasibility and advantages of screw corridors parallel to the sagittal plane (SPC) of the C2 for transpedicular fixation.

Summary of Background Data: 

A total of 125 patients were enrolled for analysis, and the 3D model of the C2 for the 125 patients were reconstructed and analyzed.

Methods: 

The SPC screw and the corridor of the general pedicle (GPC) screw of both sides were inserted into these C2 models. The anatomic parameters of the SPC and GPC, including the inner circle diameter, length of the corridors, medial angle and cephalad angle, were measured and compared. The anatomic location of the entry point for the SPC screw was evaluated.

Results: 

The diameter of the SPC averaged 5.5±1.8 mm; 81.2% (203/250) were larger than 4 mm. There was no significant difference between the SPC and GPC in diameter or percentage of diameter greater than 4 mm. There was a significant difference between the length of the SPC (25.3±2.4 mm) and the GPC (27.4±2.2 mm). The cephalad angle was 51.6±6.9° for the SPC and 43.3±4.4° for the GPC, and there was a significant difference between the SPC and GPC. The entry point of the SPC screw was located on the cortical crest at the lower 1/4 of the lamina and located to the lower and inner side of the GPC screw entry point.

Conclusion: 

It is feasible for most patients to accommodate an SPC screw with a diameter of 3.5 mm. All SPC screws crossed the pedicle completely. The optimal entry point of the SPC screw was located on the cortical crest of the axial lamina.

中文翻译：

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用于经椎弓根固定的平行于矢状面的新型 C2 螺钉通道 - 一项 3D-CT 研究

学习规划： 

一项 3D-CT 研究。

客观的： 

研究平行于C2矢状面（SPC）的螺钉通道用于经椎弓根固定的可行性和优势。

背景数据摘要： 

共有 125 名患者被纳入分析，并对 125 名患者的 C2 3D 模型进行了重建和分析。

方法： 

将两侧的 SPC 螺钉和普通椎弓根 (GPC) 螺钉的通道插入这些 C2 模型中。测量并比较SPC和GPC的解剖参数，包括内圆直径、走廊长度、内侧角和头侧角。评估了 SPC 螺钉进入点的解剖学位置。

结果： 

SPC的直径平均为5.5±1.8 mm；81.2% (203/250) 大于 4 毫米。SPC 和 GPC 在直径或直径大于 4 mm 的百分比方面没有显着差异。SPC 的长度 (25.3±2.4 mm) 和 GPC (27.4±2.2 mm) 之间存在显着差异。SPC头侧角为51.6±6.9°，GPC头侧角为43.3±4.4°，SPC与GPC有显着差异。SPC螺钉的进入点位于椎板下1/4的皮质嵴上，位于GPC螺钉进入点的下内侧。

结论： 

对于大多数患者来说，容纳直径为 3.5 mm 的 SPC 螺钉是可行的。所有 SPC 螺钉完全穿过椎弓根。SPC 螺钉的最佳进入点位于轴向椎板的皮质嵴上。