基于数字化设计和3D打印胫骨近端骨折内固定的关键技术

Key techniques of internal fixation for proximal tibial fractures based on digital design and three-dimensional printing

背景:前期实验已经完成了胫骨近端骨折三维重建复位及数字钢板设计、胫骨近端接骨板标准件库的建立以及3D打印后的手术模拟。目的:在前期研究基础上,探讨数字化设计结合3D打印模型进行标准件库接骨板、螺钉在胫骨近端骨折中导航内固定置入方法的可行性及准确性。方法:采集20例临床胫骨近端骨折患者连续薄层CT扫描的Dicom格式图像,分别导入Mimics软件予以三维重建、骨折复位。从标准件库中选择接骨板、螺钉虚拟内固定,设计带钉道的导航模块。3D打印骨骼、接骨板、导航模块,进行骨骼模型内固定手术,导航放置螺钉、接骨板,观察导航模块卡位、板钉位置情况,以术后外观、CT扫描评价效果。结果与结论:20例骨骼模型术后均行CT扫描重建,结合外观,显示接骨板位置、螺钉的进钉点,进钉方向、长度、直径均与Mimics软件中模拟预设的一致。导航模块和相对应的胫骨近端骨性结构贴合紧密,嵌合度良好,在应用时卡位及稳定性良好,可以很好指引接骨板放置、螺钉置入。提示:在导航模块的辅助下,胫骨近端骨折标准件库接骨板内固定置入准确率高,基于数字化设计和3D打印的标准件库接骨板数字化内固定技术有望良好实现骨科内固定物置入导航。

BACKGROUND：Preliminary experiments have performed three-dimensional（3D） reconstruction of proximal tibial fractures,digital steel plate design,the establishment of the proximal tibia plate standard parts library and the operation simulation of 3D printing.OBJECTIVE：To explore feasibility and accuracy of standard parts library plates and screws in the proximal tibial fracture internal fixation navigation in digital design combined with 3D printing model on the basis of preliminary studies.METHODS：Dicom format images of continuous thin layer CT scanning were collected in 20 cases of proximal tibial fractures,and uploaded in Mimics software for 3D reconstruction and fracture reduction.Plate and screw selected from standard part library were used for virtual fixation.Navigation module with screw channel was designed.3D printing skeleton,bone plate,and navigation module were used for skeleton model and internal fixation.Screw and plate were placed by navigation.Navigation module card,nail and board position were observed.Postoperative appearance and CT scanning were utilized to assess outcomes.RESULTS AND CONCLUSION：After CT scanning and reconstruction in 20 skeleton models,in combination with appearance,the position of plate,screw insertion point,the direction,length and diameter of the screw were consistent with that in Mimics software.The navigation module and the corresponding proximal end of the tibia were closely bonded with good fitting degree.In the application,card slots and stability were good,and could perfectly guide plate and screw placement.These reuslts suggest that with the aid of navigation module,standard parts library plate internal fixation for proximal tibia fracture has high accuracy.On the basis of digital design and 3D printing,digital internal fixation technology of standard parts library plate is expected to achieve good implant navigation in the department of orthopedics.