经椎板关节突螺钉固定的X线解剖学研究

X-ray anatomy of the translaminar facet screws

目的：总结 X 线透视下经椎板关节突螺钉（TLFS）成功置入时的正位、侧位、斜位影像学标准,为临床置钉提供影像学参考。方法6具成人防腐保存椎体标本（L2~ S1）,男5具、女1具,年龄31~61岁,均经 X 线摄片排除畸形、骨折、肿瘤及其他腰椎病变。直视下 L3/4、L4/5、L5/ S1随机单侧置入4 mm 螺钉,TLFS 进钉点选择在一侧椎板与棘突交界中下1/3处向后0.5 cm,外倾角和下倾角为 CT 片和 X 线片测量所得,以 X 线透视安全置入 TLFS 全过程,并分析其标准腰椎前后位、侧位和斜位 X 线影像特征。结果 TLFS 进针完成满意后,正位片显示钉尖位于下位椎弓根投影外上缘与横突上缘之间,侧位示钉尖位椎弓根后上缘,斜位片示钉尖过下位小关节间隙中点,至上关节突投影前缘。结论术中 X 线透视可能为 TLFS 置入的准确性和安全性提供重要帮助和参考。

Objective To define the radiographic characteristic for successful placement of translaminar facet screws （ TLFS）. Methods Six human cadaveric specimen of spine （ L2 - S1 ） were obtained including 5 males and 1 female, of age 31 - 61, with deformities, fractures, tumors and other lumbar spine lesions excluded by X Ray imaging. TLFS were placed randomly in the lumbar spine from L3 / 4 to L5 / S1 unilaterally, and fluoroscopic images were used to define the appropriate radiographic parameters for safe placement of the screws during operation. Results The radiographic views were identified to gain proper TLFS placement. In anterior-posterior X-ray view, the tip of screw was located between the transverse process and the projection of pedicle. In lateral X-ray view, the tip of screw was located above the posterior site of pedicle. In the standard oblique X-ray view, the tip of screw was located at the front of superior articular process, and the screw pass through the midpoint of articular space. Conclusions This study defines radiographic criteria which can provide assistance for placement of TLFS during operation.