Feasibility study of a novel screw insertion technique for safe placement of anterior transpedicular screw series in the lower cervical spine

To investigate the feasibility of a novel screw insertion technique for the safe placement of anterior transpedicular screw (ATPS) and anterior transpedicular root screw (ATPRS) in the lower cervical spine. From January 2023 to May 2024, 40 cervical CT scans of healthy individuals (18 males and 22 females) were selected from Ningbo No.6 Hospital and confirmed to have no obvious defects. The data were imported into Mimics software for three-dimensional reconstruction, and physical models were constructed using a 3D printer. Forty cervical spine (C3–C7) models were randomly assigned to either a control group ( n = 20) or an experimental group ( n = 20). In the control group, ATPRS and ATPS (50 screws each, 100 total) were inserted using a freehand technique. In the experimental group, ATPRS and ATPS (50 screws each, 100 total) were inserted using the novel screw insertion technique (screw axial fluoroscopy). CT scans were used to evaluate screw placement safety postinsertion. A total of 200 screws were placed in the 40 cervical models. Screw safety was graded according to the Neo classification. The safety rates (Grade 0 + 1) for ATPS were 66% in the control group and 90% in the experimental group (GEE: OR = 4.64, 95% CI: 1.48–14.52; P = 0.007). For ATPRS, the safety rates were 86% in the control group and 96% in the experimental group (GEE: OR = 3.91, 95% CI: 0.79–19.36; P = 0.103). In this 3D-printed lower cervical spine model, the screw axial fluoroscopy technique significantly improved the radiographic safe placement rate for ATPS. For ATPRS, the observed improvement was a numerical increase that did not reach statistical significance. However, because the experimental setup did not reproduce the soft-tissue and neurovascular constraints of actual surgery, the clinical safety of this technique remains to be determined. The next logical step should be cadaveric validation under realistic surgical conditions before any clinical application.