寰椎椎弓根螺钉固定技术的改进研究

目的 探讨寰椎椎弓根螺钉的置钉方法. 方法 以电子游标卡尺测量48具干燥寰椎标本的相关解剖学数据;并依据寰椎椎弓根的形态对寰椎进行分类,提出了针对不同类型寰椎的各种椎弓根螺钉置钉方法. 结果 钉道处椎动脉沟底骨质厚度小于螺钉直径3.5mm的占16.7%(8/48),其中4.2%(2/48)厚度小于螺钉半径1.75mm.将寰椎分为普遍型(占83%)、轻度变异型(占13%)和重度变异型(占4%). 结论 对于寰椎后弓高度偏小的患者,可以部分经寰椎后弓或跨越寰椎后弓实现寰椎的椎弓根螺钉固定,进钉位置的确定应以术前三维CT重建和术中探查结合考虑.

An anatomic study of the pedicle screw fixation

Objective To improve the method of atlas pedicle screw fixation. Methods The anatomic data related to pedicle screw fixation were measured on 48 dry atlas specimens with an electronic caliper.Classification of the atlas was done according to the pedicle morphology. Results The mean thickness of the vertebral artery groove at the entry path was less than 3.5mm (the screw diameter)in 16.7% (8/48)of the specimens,and less than 1.75mm(the screw radius)in 4.2%(2/48). Conclusions For the patients whose atlas posterior arch is not high enough for a pedicle screw,we can drill partly through or overpass the atlas posterior arch to achieve pedicle screw fixation.The entry point should be ascertained by preoperative 3D CT reconstruction and the exploration during the operation.