数字化导航模板在颈椎椎弓根螺钉置入中的应用

Application of digital navigation template for cervical pedicle screw placement

中文关键词:  椎弓根螺钉  颈椎  个体化导航模板  计算机辅助设计  快速成型

英文关键词:Pedicle screw  Cervical vertebra  Individual navigation templates  Computer-aided design  Rapid prototyping

中文摘要:

  【摘要】 目的：评价个体化导航模板辅助颈椎椎弓根螺钉置入的准确性和安全性。方法：2010年8月~2013年8月，对25例需要行颈椎椎弓根螺钉内固定的患者术前行64排螺旋CT连续扫描，计算机重建颈椎三维模型、设计颈椎椎弓根的最佳进钉通道，获取每个颈椎椎板的解剖形态，设计与颈椎椎板吻合的反向模板，并模拟螺钉的最佳进钉通道，形成单侧定位导向孔的导航模板。利用3D打印技术打印颈椎模型和导航模块，通过术前模拟置钉测量出每个椎弓根的螺钉通道长度及椎弓根宽度，术中采用导航模板辅助置入椎弓根螺钉，术后行CT扫描评价螺钉位置，记录有无与螺钉置入相关的并发症。结果：利用导航模板辅助置入颈椎椎弓根螺钉共164枚，其中152枚完全在椎弓根内，4枚螺钉穿破椎弓根内侧皮质，8枚螺钉穿破椎弓根外侧皮质，无椎弓根上方、下方穿破的螺钉，未发现与置钉相关的椎动脉、神经根和颈髓等损伤的症状。结论：个体化导航模板辅助颈椎椎弓根螺钉置入可以提高置钉的准确率，增加颈椎手术的安全性。

英文摘要:

  【Abstract】 Objectives: To evaluate the accuracy and safety of the application of individulalized navigation template for cervical pedicle screw placement. Methods: From August 2010 to August 2013, twenty-five patients required cervical pedicle screw fixation were studied. Preoperative 64-slice spiral CT scan was applied. by computer, three-dimensional cervical spine models were reconstructed, the optimal trajectory of cervical pedicle screws were designed, and the morphological feature of the posterior cervical spine elements were extracted. The reverse template was designed according to morphological feature. Then, the optimal trajectory and the template were fused into unilateral navigation template. The cervical spine model and the navigation template were created by rapid prototyping and 3D print technique. The length of each pedicle screw channel and the width of pedicle were measured. Cervical pedicle screws were inserted with the assistance of navigation templates. Postoperative CT scan was used to evaluate the screw position. The complications associated with screw placement were recorded. Results: Total 164 screws were inserted with the assistance of individual navigation templates. 152 screws were placed entirely within the pedicle, 4 screws perforated the medial cortex of pedicle, and 8 screws perforated the lateral cortex of pedicle. No screw perforated through the superior and inferior wall of the pedicle. No pedicle screws had placement-related complications, such as the injury of vertebral arteries, nerve roots and spinal cord occurred. Conclusions: The individualized navigation template-assisted internal fixation is a feasible and safe method for cervical pedicle screw placement.