透视下分步引导上中胸椎椎弓根螺钉安全植入实验研究

目的：探索C形臂X线监测引导上中胸椎椎弓根螺钉植入的的方法,并评定其准确性与安全性。方法：①取6具正常成人T1-T8脊椎骨架标本,分解出单个椎体,导针沿椎弓根轴线进针,分别于进针点、针前端位于椎弓根中部、椎体后缘及椎体前缘皮质下,通过C形臂X线透视,记录、分析椎弓根轴线导针在进针点及不同进针深度时在正侧位透视图像上导针前端的位置,以及相关位置对应关系变化规律。②按上述椎弓根轴线导针C形臂X线透视监测对应位置变化规律,作为C形臂X线透视下分步引导上中胸椎椎弓根螺钉安全植入的方法。取6具T1-T8脊柱标本,C形臂X线机引导下分步植入椎弓根螺钉96枚,然后将脊椎标本作CT扫描,判定椎弓根螺钉位置。结果：根据CT扫描结果,优（椎弓根螺钉安全位于椎弓根内者）90枚,可（螺钉穿破椎弓根内或外侧骨皮质较少,突破在2mm以内者）6枚,差（螺钉穿破椎弓根内外骨皮质较多,突破在2mm以上）0枚。结论：C形臂X线透视下分步引导上中胸椎椎弓根螺钉植入,是一种能提高上中胸椎椎弓根螺钉植入的简单经济、确实可行的方法。

Research on safe implantation of upper-middle thoracic pedicle screws under the X-ray perspective

Objective ： To explore the method of implanting upper-middle thoracic pedicle screws under monitoring by X- ray and evaluate accuracy and safety. Methods：（1）Six normal adult thoracic spine samples （T1-T8）were selected, from which single spine units were separated. A surgical probe went in along the pedicle axis. By C-shaped arm X-ray ,the four probe positions were recorded：at the entering point, the front end of the probe in the middle of the pedicle, at the pack of the spine, and under the cortex of the front of the spine. The position of the front end of the probe at the entering point, and the front end of the probe at different depth at central-side perspective position were analyzed. The related positions and their corresponding changing rules were also analyzed. （2）Based on the changing rules mentioned above,different steps were adopted under the guidance of the C-shaped arm X-ray, to safely implant upper-middle thoracic pedicle screws. First, six 1-T8 spine samples were used,and under the guidance of the C-shaped arm device,96 pedicle screws were implanted. After the operation,the sping samples were scanned through CT,and the positions of the screws were determined. Results：According to the result of the CT scanning,the result were excellent （the screw was safely inside the pedicle）in 90 screws;Medium （the screw penetrated a little of the inside or outside bone cortex,within 2 mm）in 6;No one was bad （the screw penetrated a lot, more than 2 mm）. Conclusion ：The implantation of upper-middle thoracic pedicle screw under the guidance of the C-shaped arm X-ray perspective is a simple and feasible method ,and improve the accuracy and safety.