选择腰椎椎弓根螺钉长度的放射解剖学研究

Radiological anatomy study in selecting the length of pedicle screw in lumbar spine

目的 :探讨在腰椎侧位片及CT片上推算椎弓根螺钉长度的方法 ,为临床提供参考。方法 :随机在 3 0个腰椎骨标本上用 1mm软钢丝在椎弓根最狭窄处缠绕 ,按人字嵴进钉方法打入椎弓根直钢丝 ,拍正侧位片、横断面片及椎弓根CT扫描 ,分别在标本、CT及侧位片上测量椎弓根螺钉长度 ,三组数据比较。结果 :腰椎侧位片上测量的自关节突关节间隙下缘至椎体前缘距离乘以 0 .83即是螺钉长度 ,椎弓根CT扫描测量其长度更为准确。结论 :正常拍照条件下 ,用腰椎侧位片和椎弓根CT片可准确地推算螺钉长度 ,具有临床实用意义。

Objective: To discuss how to determine the length of pedicle screw according to lateral X ray film and CT film in lumbar spine.Methods: Thirty vertebra were winded with the wire 1.0mm in diameter, and were inserted pedicle screws with standard methods.The anteroposterior, lateral and superoinferior roentgenograph and CT scanning through pedicle screw were performed in all specimens.Results:The length of pedicle screw could be obtain accurately on CT and lateral X ray film, and the length was equal to multiply by 0.83 the distance from the anterior cortex of vertebral to the facet joint.Conclusion: The length of pedicle screw can be accurately obtained from CT and lateral X ray films.It is a simple and easy way to select the length of screw in lumbar spine.