Robotic-Assisted Cervical Pedicle Screw Placement With Uniform 5.5 mm Rods Crossing the Cervicothoracic Junction: Accuracy and Technical Feasibility.

STUDY DESIGN: Retrospective case series. OBJECTIVE: To evaluate the accuracy and safety of robotic-assisted cervical pedicle screw placement using the SpineVidya C-TEK system with uniform 5.5 mm rods across the cervicothoracic junction. SUMMARY OF BACKGROUND DATA: The cervicothoracic junction (CTJ) represents a biomechanical transition zone where traditional cervical constructs require rod diameter transitions, introducing mechanical weakness. The C-TEK system features an enlarged tulip design accommodating 5.5 mm rods with 4.0 mm diameter cervical pedicle screws, eliminating the need for tapered rods or connectors at the CTJ. METHODS: Twenty-six consecutive patients (282 screws) underwent robotic-assisted C-TEK cervical pedicle screw placement crossing the CTJ between April 2024 and June 2025. All procedures utilized the MazorX Stealth Edition robotic system with O-arm intraoperative CT imaging. Two blinded observers assessed screw accuracy using the Gertzbein-Robbins classification. Clinical outcomes and complications were evaluated. RESULTS: Mean age was 54.1 years. In this preliminary series, all 282 screws achieved clinically acceptable placement (grades A-B; 100% in this cohort). Perfect placement (grade A) was achieved in 276 screws (97.9%), with grade B breach in 6 screws (2.1%). No grade C, D, or E breaches occurred. At the cervicothoracic junction levels (C7, T1, T2), 78 screws maintained clinically acceptable accuracy. Interobserver reliability was excellent (κ=0.94). No vertebral artery injuries, permanent neurological deficits, or hardware failures occurred. Illustrative cases demonstrated feasibility across diverse pathologies including dropped head syndrome, dystrophic scoliosis, and revision scenarios. CONCLUSIONS: Robotic-assisted C-TEK cervical pedicle screw placement demonstrates high accuracy and technical feasibility for uniform 5.5 mm rod constructs crossing the CTJ without rod diameter transitions or connectors. These preliminary results from a single-center experience support further investigation, including comparative studies with traditional dual-diameter systems. LEVEL OF EVIDENCE: Level IV.