This is a historical, multi-site analysis. The purpose of this study was to examine the variables associated with robot-assisted pedicle screw placement and the relative contributions of these variables to the overall accuracy of this procedure. According to reports, the accuracy with which pedicle screws may be placed during robotic surgery has greatly surpassed that of traditional methods. The precision with which robotic pedicle screws are inserted may be affected by a number of factors. As far as researchers know, no study has thoroughly examine these variables. Together, the radiological and clinical data from 3 different institutions paint a clearer picture. To evaluate the precision of the screw placement, all 3 hospitals collected computerized tomographic CT scans both before and after surgery. 

The important metric was the robot’s reliability in inserting pedicle screws. After doing a multivariate regression analysis, the authors were able to identify the most important patient- and screw-related variables, as well as the proportional contribution of each, in determining the overall accuracy of the procedure. Furthermore, an ordinal regression analysis was carried out to examine the impact of various factors on the precision of screws placed by robots, as measured by the Gertzbein-Robbins grading system (GRS). Overall accuracy variation, as assessed by offsets between the put and planned screws, was only 18% due to all the examined variables combined. Variations in screw offsets were also marginally influenced by parameters such as patient obesity, construct length, patient gender, surgical experience, and spinal level. 

Log odds for GRS grades varied significantly by gender (0.62, 95% CI: 0.38-0.85), age (0.02, 95% CI: 0.01-0.03), construct length (0.07, 95% CI: 0.02-0.11), screw diameter (0.55, 95% CI: 0.39-0.71), and screw length (0.03, 95% CI: 0.01-0.05). These variables also had a substantial relationship with the precision with which screws were inserted, but they contributed very little to the overall accuracy variability (only about 7%). The robustness of the robotic navigation system employed in this work means that the accuracy of screws placed with robotic assistance, as rated by GRS or measured offsets between planned and placed screw trajectories, is minimally affected by different patient-related or screw-related variables.

Source: journals.lww.com/spinejournal/Fulltext/2022/12010/Factors_Affecting_the_Accuracy_of_Pedicle_Screw.1.aspx