A Clinical Study Of Novel Three-Dimensional Printing "Semi-Adhered Bone Guide Template" Assisted Percutaneous Sacroiliac Screw Insertion

Objectives:To introduce a novel 3D printed semi-attaching bone guide template for the precise and rapid placement of percutaneous sacroiliac screws and to evaluate the accuracy of the guide template.Methods:From July 2017 to September 2019,a retrospective analysis was performed on 5 patients with posterior pelvic ring disorder,all of whom were from the department of orthopedics,union hospital affiliated to tongji medical college,huazhong university of science and technology.Based on preoperative pelvic computed tomography data,a well-designed customized pelvic model with individualized channels and a guide template were created using 3D reconstruction software and 3D printing.During preoperative simulation and actual surgery,the guide template was matched with a positioning marker on the iliac crest.A guide wireand then sacroiliac screw was inserted along the guide column.The accuracy of the guide template was evaluated by recording the operation time,radiation exposure,postoperative X-ray,CT and wire deviation.Results: During the preoperative simulated operation,the guide template was well matched with the iliac crest of the pelvic model,and the guide wire was successfully inserted into the channel of the model.The intraoperative guide template was also successfully matched with the iliac crest,and the guide needle was successfully inserted into the sacroiliac channel..The mean time required for sacroiliac screw placement was 19.6±3.26 min.The radiation exposure per screw was 49.76±7.84 seconds,Postoperative X-ray and CT showed that all screw was in good position.The mean deviation distance between the actual and planned screw position was 3.33±1.17 mm at the midline of the spinal canal,2.45±1.00 mm in the nerve root tunnel zone and 1.94±0.82 mm at the entry point,with a mean deviation angle of 1.8±1.06°.Conclusion: The novel 3D-printed semi-adherent bone guide template could use the iliac crest as a positioning marker and achieve minimally invasive percutaneous sacroiliac screw insertion rapidly,safely,and accurately,while greatly decreasing operative time and radiation exposure.