Li Chao, Niu Guo-Qi, Jiang Wei-Li, Chen Hui, Liu Lu-Tan, Zhou Qian-Kun, Cheng Jia-Wei
Department of Orthopaedics, the Second Affiliated Hospital of Bengbu Medical College, Bengbu 233000, Anhui, China.
Zhongguo Gu Shang. 2020 Jul 25;33(7):649-54. doi: 10.12200/j.issn.1003-0034.2020.07.011.
To evaluate accuracy and safety of individualized 3D printing guided template for thoracolumbar pedicle screw placement in patients with ankylosing spondylitis.
From January 2016 to September 2019, thoracolumbar spine three-dimensional CT data of 8 patients with ankylosing spondylitis were included, Mimics 17.0 and ideaMaker computer software were applied to design thoracolumbar pedicle screw guided template of patients with AS, physical model of all patients (T-L)were printed by 3D printer, 2 parts in each patient, and divided into guide-plate-assisted screw group (experimental group) and free-hand nail group (control group). Thoracolumbar pedicle screws of both groups were placed by the same spinal surgeon. The accuracy of pedicle screw placement between two groups were evaluated according to results of postoperative CT, the accuracy of the fixation of thoracolumbar pedicle screw was divided into 4 grades, grade 0 and 1 screws were acceptable nails, grade 2 and 3 screws were unacceptable nails. The diameter and length of pedicle screws, the distance between entry point and posterior median line designed by preoperative 3D printing were compared with actual use in operation.
Twenty three blocks of thoracolumbar 3D printing screw of ankylosing spondylitis guided templates were designed and printed in guide-plate-assisted screw group, 46 screws were inserted and 44 screws were accepted. The time of implanting a screw into thoracolumbar pedicle was (4.20±1.15) min, the frequency of X-ray was (5.00±1.25) times and the average adjustment times of screw and Kirschner needle during screw placement was (1.76±1.32) times. In the control group, 46 nails were placed by traditional surgical method and 30 screws were accepted. The time of implanting a screw into thoracolumbar pedicle was (14.67±2.23) min, the frequency of X-ray fluoroscopy was (14.46±2.21) times and the average times of Kirschner needle adjustment was (4.76±3.39) times. The success rates between experimental group and control group were 95.65%(44 / 46) and 56.22%(30 / 46) respectively, and had statistical difference (χ=13.538, <0.05). There was no significant difference in diameter, length of pedicle screws and the distance of posterior median line between virtual designed by 3D printing before operation and actual situation in opertaion (>0.05). The operation time of inserting a single screw, the times of X-ray fluoroscopy, and the average times of adjustment screw and Kirschner needle in experimental group were significant less than those in control group(<0.01).
The personalized guide template assisted the thoracolumbar fixation designed by 3D printing could significantly improve safety, accuracy and efficiency of surgery, especially suitable for thoracolumbar vertebral bodies requiring posterior pedicle screw fixation for fracture or dislocation with AS.
评估个体化3D打印导向模板在强直性脊柱炎患者胸腰椎椎弓根螺钉置入中的准确性和安全性。
纳入2016年1月至2019年9月8例强直性脊柱炎患者的胸腰椎三维CT数据，应用Mimics 17.0和ideaMaker计算机软件设计强直性脊柱炎患者胸腰椎椎弓根螺钉导向模板，通过3D打印机打印所有患者胸腰椎（T-L）实物模型，每个患者2个部件，分为导向板辅助螺钉组（实验组）和徒手置钉组（对照组）。两组胸腰椎椎弓根螺钉均由同一位脊柱外科医生置入。根据术后CT结果评估两组椎弓根螺钉置入的准确性，胸腰椎椎弓根螺钉固定准确性分为4级，0级和1级螺钉为可接受螺钉，2级和3级螺钉为不可接受螺钉。比较术前三维打印设计的椎弓根螺钉直径、长度以及进针点与后正中线距离与术中实际使用情况。
导向板辅助螺钉组设计并打印了23个强直性脊柱炎胸腰椎3D打印螺钉导向模板，置入螺钉46枚，44枚螺钉合格。胸腰椎椎弓根螺钉置入时间为（4.20±1.15）分钟，X线透视次数为（5.00±1.25）次，置钉过程中螺钉及克氏针平均调整次数为（1.76±1.32）次。对照组采用传统手术方法置入46枚螺钉，30枚螺钉合格。胸腰椎椎弓根螺钉置入时间为（14.67±2.23）分钟，X线透视次数为（14.46±2.21）次，克氏针平均调整次数为（4.76±3.39）次。实验组与对照组成功率分别为95.65%（44/46）和56.22%（30/46），差异有统计学意义（χ=13.538，<0.05）。术前3D打印虚拟设计的椎弓根螺钉直径、长度及后正中线距离与术中实际情况比较，差异无统计学意义（>0.05）。实验组单枚螺钉置入手术时间、X线透视次数及螺钉与克氏针平均调整次数均明显少于对照组（<0.01）。
3D打印设计的个体化导向模板辅助胸腰椎固定可显著提高手术安全性、准确性及效率，尤其适用于强直性脊柱炎合并骨折或脱位需后路椎弓根螺钉固定的胸腰椎椎体。
