Cirq® robotic assistance for thoracolumbar pedicle screw placement – feasibility, accuracy, and safety

INTRODUCTION: New technologies providing higher degree of precision, less risk for damage and less harmful exposure to radiation are necessary for correct transpedicular screw trajectory, but their efficacy should be evaluated. RESEARCH QUESTION: Evaluate the feasibility, accuracy and safety of Brainlab Cirq® navigated robotic arm assistance for pedicle screw placement in comparison to fluoroscopic guidance. MATERIAL AND METHODS: Group I “Cirq® robotic-assisted group” – 97 screws in 21 prospectively analyzed patients. Group II “Fluoroscopy-guided group” – 98 screws in 16 consecutive patients analyzed retrospectively. Comparative evaluations included screw accuracy on Gertzbein-Robbins’s scale and fluoroscopy time. Time per screw and subjective mental workload (MWL) measured with the raw NASA task load index tool were assessed for Group I. RESULTS: 195 screws were evaluated. Group I: 93 screws grade A (95.88%); 4 grade B (4.12%). In Group II, 87 screws grade A (88.78%); 9 grade B (9.18%); 1 grade C (1.02%); 1 grade D (1.02%). While the screws placed using the Cirq® system were more accurate overall, there was no statistical significance between the two groups, p=0.3714. There was no significant difference in operation length or radiation exposure between the two groups, however with the Cirq® system the radiation exposure for the surgeon was limited. Reduction in time per screw (p<0.0001) and in the MWL (p=0.0024) correlated with the surgeon’s experience with Cirq®. DISCUSSION AND CONCLUSION: The initial experience suggests that navigated, passive robotic arm assistance is feasible, at least as accurate as fluoroscopic guidance, and safe for pedicle screw placement.