前路经寰枢关节螺钉内固定术的三维CT血管造影多平面测量及临床研究

3D-CTA multi-plane measurements and clinical study on anterior C1-C2 transarticular screw fixation

目的探讨前路经寰枢关节螺钉内固定术钉道安全性及临床疗效评估。方法对21例创伤性寰枢椎不稳定患者行前路经寰枢关节螺钉内固定术并随访，术后行x线及CTA检查，应用三维CT血管造影（3D—CTA）及AW三维测量软件测量螺钉置入的角度、螺钉在不同平面与椎动脉及椎管的距离，所得数据进行统计学分析。结果全部病例置钉范围均在矢状面上外偏（9°-22°）平均17°，冠状面上后倾（12°～29°）平均21°，螺钉长度（19～30mm）平均24．5mm，直径3．5mm，术中均未发生椎动脉与脊髓损伤；20例获得随访，时间5个月～9年，平均20个月，术后复查示螺钉位置良好，无松动及断钉，寰枢关节植骨融合率为95．0％，术后临床症状均不同程度改善，恢复良好。螺钉与椎动脉间最小距离位于椎动脉入寰椎横突孔平面，数值为（2．2～10．2mm），平均5．71mm，螺钉与椎管间最小距离位于椎动脉出寰椎横突孔平面，数值为（3．8—13．2mm），平均7．36mm。结论研究表明前路经寰枢关节螺钉内固定术是安全有效的。

Objective To investigate screw path safety and clinical efficacy assessment of anterior C1-C2 transarticular screw fixation. Methods 21 cases of traumatic atlantoaxial instability were treated by anterior C1-C2 transarticular screw fixation and followed up, After operation, X-ray and CTA are examed. With the application of 3D-CTA and the AW three-dimensional measurement software, the measurement of the angle of the screw placement and the distance between the screw and the vertebral artery as well as spinal canal at different plane is accessible and used for statistical analysis. Results All ＂the cases with the placement of the cancellous bone screw of which the length is from 19 to 30 mm and diameter is 3.5 mm with the lateral angulation to the sagittal plane ranged from 9° to 22 ° and the posterior angulation to the coronal plane from 12° to 29° had no trauma on vertebral artery and cervical cord during their cervical operations; 20 cases were followed up for about 5 months to 9 years with an average of 20 months. Screw position after operation review showed well with no loosening or breakage and Atlantoaxial synostosis rate was 95%. The clinical symptoms were improved to different levels and patients recovered well. The minimum distance between the screw and the vertebral artery is located inside the plane of transverse foramen of arias with an average of 5.71 mm（2. 2-10. 2 mm）. The minimum distance between the screw and the spinal canal is located outside the plane of transverse foramen of atlas with an average of 7.36 mm（3.8-13.2 mm）. Conclusion Our Research have indicated that anterior C1-C2 transarticular screw fixation is safe and effective.