Accuracy and Safety of Using Customized Guiding Templates for Cervical Pedicle Screw Insertion in Severe Cervical Deformity, Fracture, and Subluxation: A Retrospective Study of 9 Cases

Abstract

Objective: To assess accuracy and safety of self-developed customized guiding templates for cervical pedicle screw (CPS) insertion surgery.

Methods: From July 2016 to December 2017, 57 screws were implanted in 9 patients with the assistance of customized guiding templates. Customized guiding templates were manufactured from acrylonitrile-butadiene-styrene plastic material using a three-dimensional printer after establishing pedicle screw trajectories for each vertebra with the assistance of a virtual surgical planning software program, developed by our team, for the insertion of CPSs.

Results: CPSs were evaluated using the following grading system: grade 0 (contained), grade 1 (exposure), grade 2 (perforation), and grade 3 (penetration). Each patient underwent postoperative computed tomography to evaluate accuracy of screw position. Of 57 screws, 54 were graded 0, and 3 were graded 1; no screws were graded 2 or 3. No vascular or nerve injuries were noted after the operations.

Conclusions: CPSs, which provide strong biologic strength, are especially suitable for treating osteoporosis and severe deformity. However, CPS insertion remains a challenging procedure with high incidences of vascular and nerve injuries reported. The results of this study indicate that use of customized guiding templates can improve safety of CPS insertion surgery.

Keywords: Cervical pedicle screws; Cervical spondylotic myelopathy; Customized guiding template.