个体化导航模板辅助腰椎椎弓根螺钉置钉准确性实验研究

The accuracy of transpedicular screw placement assisted by individualized navigation templates in the lumbar spine

目的：探讨个体化导航模板辅助腰椎椎弓根螺钉置入的准确性。方法：根据10具尸体腰椎（L1～L4）标本术前CT资料，利用逆向工程原理及快速成型技术设计制造出个体化导航模板，在尸体标本上进行个体化导航模板辅助腰椎椎弓根螺钉的置入手术，术后行CT断层扫描评价螺钉在椎弓根及椎体内的位置。结果：共应用40个个体化导航模板，辅助置入腰椎椎弓根螺钉80枚。CT扫描发现所有螺钉进钉点准确，进钉方向适当；全部螺钉均准确置入相应椎弓根及椎体内，无穿破椎弓根皮质及椎体前方的螺钉。结论：个体化导航模板辅助腰椎椎弓根螺钉置钉准确性高，操作简单，为腰椎椎弓根螺钉的准确置入提供了一种新的可供选择的方法。

Objective ：To investigate the accuracy of transpedicular screw placement assisted by individualized navigation templates in the lumbar spines.Method：The pre-operative CT data of ten human lumbar spines were used to design and generate a novel individual lumbar navigation templates by reverse engineering and rapid prototyping,after that the templates were used to guide lumbar pedicle screw placement in the specimens.Subsequently,CT scans were performed to evaluate screw orientation associated with the pedicle axis.Result：80 lumbar pedicle screws assisted by 40 individual navigation templates were implanted in the lumbar spines.All screws were completely contained within the pedieles.No screw broke through medial,lateral,superior or inferior cortex of pedicle and anterior cortex of vertebral body.The anchor point and orientation of all screws were aceurate.Conclusion：Transpedicular screw placement assisted by individualized lumbar navigation templates is highly accurate and simple which is a new alternative to conventional technique.