3D打印导航模板在辅助寰枢椎椎弓根螺钉置入中的应用价值

The applied value of 3D printed navigational guiding template in pedicle screw placement

中文关键词:  寰枢椎  椎弓根螺钉  3D打印导航模板  计算机辅助设计  快速成型技术

英文关键词:Atlantoaxial vertebrae  Pedicle screw  3 dimensional printing model  Computer-assisted  Rapid prototyping technology

中文摘要:

  【摘要】 目的：探讨三维（3D）打印导航模板辅助寰枢椎椎弓根螺钉置钉的价值。方法：回顾性分析2013年1月~2015年10月我院收治的43例寰枢椎骨折和/或脱位患者，均行后路寰枢椎切开复位内固定术。按手术方式不同分为3D打印导航模板组（19例）和传统置钉组（24例）。3D打印导航模板组术前将患者的颈椎CT数据导入Mimics 17.0软件，行3D重建并设计带钉道的导航模板后打印、消毒；术中将导航模板与置钉椎体贴合紧密后，通过定位孔钻孔、置钉。传统置钉组在C型臂X线机透视下徒手置钉。统计并对比两种置钉方法的准确率，通过测量并比较术前预设钉道角度与术后实际钉道角度差异评估进针角度的精确性。比较两组的置钉时间、手术时间、透视次数、术中出血量及患者颈肩部疼痛视觉模拟评分（visual analogue scale，VAS）和日本骨科协会（Japanese Orthopaedic Association，JOA）颈椎神经功能评分的差异情况。结果：两组患者在性别、年龄、临床诊断、病变节段、合并症及术前是否牵引复位方面均无统计学差异（P＞0.05）。19例3D打印导航模板辅助置入椎弓根螺钉68枚，置钉准确率94.1%，置钉时间2.2±0.4min/枚，透视次数4.6±1.1次，手术时间197±41min，术中出血量395±64ml；传统徒手置钉组置入椎弓根螺钉76枚，置钉准确率76.3%，置钉时间3.4±0.7min/枚，透视次数9.4±2.7次，手术时间245±67min，术中出血量552±79ml。两组置钉准确率、置钉时间、透视次数、手术时间及术中出血量均有统计学差异（P<0.05）。3D打印导航模板组的内倾角及头倾角与预设值无统计学差异（P＞0.05），置钉角度的精确性明显优于徒手置钉组（P<0.05）。术后3d、6个月及12个月患者颈肩部VAS及颈椎JOA评分较术前明显好转（P<0.05），而术后6个月及12个月两组间颈肩部VAS及颈椎JOA评分无统计学差异（P＞0.05）。结论：3D打印导航模板辅助寰枢椎椎弓根置钉可提高置钉准确率，同时还可缩短置钉时间、手术时间，减少透视次数和术中出血量。

英文摘要:

  【Abstract】 Objectives: To investigate the applied value of 3D printed navigational guiding template in pedicle screw placement. Methods: From June 2013 to October 2015, data from 43 cases who had undergone opening reduction and internal fixation of atlantoaxial vertebra with pedicle screw placement were retrospectively analyzed. All the patients were divided into 3D printed navigational guiding template assisting pedicle screw placement group and traditional pedicle screw placement group. The accuracy of screw channel was evaluated by comparing differences of preoperative and postoperative indexes in 2 groups. The comparisons of operation time, intraoperative blood loss, the number of intraoperative fluoroscopy, the accuracy and the time of screw placement were performed. Besides, cervical spine visual analogue score(VAS) and spinal function score of Japanese Orthopedic Association(JOA) were also compared between the two groups. In addition, postoperative trajactories of pedicle screws were measured after the positions of preoperative and postoperative 3D atlantoaxial models in a redefining coordinate. Briefly, all the 19 patients in 3D printed navigational guiding template group had preoperatively performed CT scanning and the data were imported into Mimics 17.0 software. Afterward, the 3D models of cervical vertebrae were reconstructed and the optimal trajectory of virtual navigational template with guiding hole was established. After navigational template was manufactured by 3D printing and sterilizing, it was used to assist with the placement of pedicel screw intraoperatively. Results: There were no significant differences in general data of the two groups which included age, sex, clinical diagnosis, lesion segment, complication and proportion of preoperative traction and reduction(P＞0.05). All the 19 patients in 3D printed navigational guiding template group were totally placed 68 pedicle screws, with the accuracy of 94.1%, pedicle screw placement time was 2.2±0.4min, operation time was 197±41min, intraoperative blood loss was 395±64ml and intraoperative fluoroscopy number was 4.6±1.1 times. All the 24 cases in traditional pedicle screw placement group were placed 76 pedicle screws, with the accuracy of 76.3%, pedicle screw placement time was 3.4±0.7min, operation time was 245±67min, intraoperative blood loss was 552±79ml and intraoperative fluoroscopy number was 9.4±2.7 times. The differences between parameters mentioned above were all significant(P<0.05). The trajactories of pedicle screws in 3D printed navigational guiding template group had significant better results than those in traditional pedicle screw placement group(P<0.05). VAS and JOA scores of 3 days, 6 months and 12 months postoperatively were significantly improved compared with preoperative data(P<0.05), while VAS and JOA scores of postoperative 6 months and 12 months were of no significant differences between the two groups(P>0.05). Conclusions: The assistance of 3D printed navigational guiding template in guiding atlantoaxial pedicle screw placement can significantly increase the accuracy of atlantoaxial pedicle screw placement and reduce the time of screw placement, operation time, intraoperative blood loss and the number of intraoperative fluoroscopy.