一种枢椎“椎弓根”进钉技术的建立及其解剖学测量

目的通过研究枢椎的相关解剖学标记,建立枢椎＂椎弓根＂螺钉新的进钉参考标记及进钉技术。方法取40套成人枢椎干骨标本,测量枢椎下关节突、枢椎横突孔内缘与枢椎＂椎弓根＂的位置关系,建立枢椎＂椎弓根＂螺钉新的进钉技术。结果①枢椎横突孔内缘与正中矢面的垂直距离为（18.24±1.34）mm;枢椎下关节突的中点与正中矢面的垂直距离为（17.31±1.35）mm,枢椎横突孔内缘位于枢椎下关节突中点外侧1mm处,枢椎＂椎弓根＂峡部中点位于枢椎下关节突中点内侧2.45mm处。②枢椎＂椎弓根＂新的进钉技术的内倾角为（25.03±3.82）°,上倾角为（20.00±2.34）°,螺钉在枢椎＂椎弓根＂内行走距离为（27.77±1.88mm）。结论可以采用横突孔内缘为进钉解剖学标志,枢椎下关节突中点外侧1mm及枢椎＂椎弓根＂峡部中点作为枢椎＂椎弓根＂螺钉的进钉点和进钉方向。

The establishment of a new "pedicle" screw entrance technique of axis and its anatomical measurements

Objective To set up a new ＂pedicle＂screw entrance technique with a new reference marker by analyzing the anatomy of associated landmarks on axis.Methods In order to establish a new＂pedicle＂screw entrance technique of axis,specimens of 40 sets adult dry-axial bone were collected to disclosure the relation between C2 inferior articular process,medial border of transverse foramen and C2 ＂pedicle＂of axis.Results ①The vertical distance from median plane to medial border of transverse foramen was averaged at（18.24±1.34） mm,the distance from the median plane to the midpoint of C2 inferior articular process was averaged at（17.31±1.35） mm.The medial border of C2 transverse foramen located at 1mm of lateral border of inferior articular process.The midpoint of C2 isthmus was located at 2.45mm of the medial border of midpoint of C2 inferior articular process.②In the new entrance method we developed,the introversion angle of axial ＂ pedicle＂ screws is（25.03±3.82） degree and the slope angle is（20.00±2.34） degree,screw was traveling for the distance of（27.77±1.88） mm inside the ＂pedicle＂of axis.Conclusions The medial border of transverse foramen could be used as a very convenient key anatomic landmark for screw entrance,1mm of lateral border of inferior articular process can be the enter point,and the midpoint of C2 isthmus could be guidance for entrance.