数字化导向模板辅助颈椎单开门椎管扩大成形术的可行性研究

The feasibility of digital guidance drill template assisted expansive open-door laminoplasty

目的探究数字化导向模板辅助颈椎单开门椎管扩大成形术的可行性。方法选取正常成人颈椎(C_(3-7))湿性标本10具,其中男性6具,女性4具。年龄42~67(43.6±4.2)岁。CT扫描标本后,以DICOM格式导入Mimics软件。三维建模并为单开门椎管扩大成形选取两侧骨槽位置及深度,设计导向模板后导出STL数据,最终3D打印成型。将导向模板贴附于相应的颈椎椎板后部及棘突上,在导板辅助下用磨钻分别在颈椎的开门侧和门轴侧开槽,然后从开门侧抬起椎板并固定,完成单开门椎管扩大成形。术后再次对标本进行CT连续断层扫描。记录门轴侧骨槽的内层骨皮质是否发生骨折。并再次进行三维重建,通过配对t检验比较理论与实际两侧骨槽的位置和深度的差异。结果共设计并制作了导板50个。经术后影像学评价,无门轴侧骨槽骨折的发生。C_(3-7)理论开门侧骨槽位置距中线的范围为11.8~14.4 mm,实际的范围则为11.4~14.0 mm;理论门轴侧骨槽位置距中线的范围为11.6~14.3 mm;实际的范围则为10.9~14.0 mm。理论的门轴侧深度的范围为3.0~3.8 mm,实际的范围则为3.1~3.8 mm。经统计学分析,理论与实际的开门侧骨槽位置、门轴侧骨槽位置和门轴侧骨槽深度的差异均无统计学意义(均P>0.05)。结论数字化导向模板辅助颈椎单开门椎管扩大成形术是一种可行的技术,能提高骨槽位置和骨槽深度的准确性和安全性,具有临床应用价值。

Objective To explore The feasibility of digital guidance drill templates assisted expansive open-door laminoplasty.Methods Ten specimens of normal adult cervical spine(C_(3-7))were selected,including six males and four females.The specimens aged 42-67 years,with an average age of(43.6±4.2)years.After CT scanning,the date was imported into Mimics software in DICOM format.3D models were reconstructed and the position and depth of troughs on the open side and hinge side were selected for expansive open-door laminoplasty.Drill templates were designed and exported in STL,manufactured by 3D printing finally.Then drill templates were attached to the posterior part of cervical lamina and spinous process.Under guidance of templates,troughs of both sides were conducted by using a high-speed drill.Then the lamina is elevated and instrumentations were implanted.Postoperative CT scanning was conducted to record the fracture of trough on the hinge side.3D reconstruction was performed again to compare the position and depth between theory and actual trough on both sides by paired t test.Results A total of 50 drill templates were designed and manufactured.There was no occurrence of hinge fracture after operation.In C_(3-7),the distance range between the theory position of troughs on the open side and the midline was 11.8-14.4 mm,while in actual it was 11.4-14.0 mm.The distance range between the theory position of troughs on the hinge side and the midline was 11.6-14.3 mm;in actual,it was 10.9-14.0 mm.The theory depth range of trough on the hinge side was 3.0-3.8 mm,while the actual depth was 3.1-3.8 mm.According to the statistical analysis,the difference in the position of trough on the open side,the position of trough on the hinge side and the depth of trough on the hinge side between theory and actual were not statistically significant(all P>0.05).Conclusion Digital guided template assisted open-door laminoplasty is a feasible technique,which can improve the accuracy and safety of the position and depth of the trough,and has clinical application value.