# Comparative analysis of the pedicle screw accuracy, screw revision and loosening rate and radiation exposure of robotic-guided (RG), intraoperative computed tomography (iCT)-navigation guided, and fluoroscopy guided placement technique

## TL;DR

This study compares robotic-guided, CT-guided, and fluoroscopy-guided techniques for placing spinal screws, finding that robotic guidance is most accurate and CT guidance reduces radiation exposure.

## Contribution

The study provides a comparative analysis of screw placement accuracy and radiation exposure across three surgical guidance techniques.

## Key findings

- Robot-guided screws had the highest accuracy (91.7% GRS A) and no postoperative revisions.
- iCT-based approaches reduced in-hospital radiation exposure compared to fluoroscopy.
- Fluoroscopy-guided techniques had the highest revision rates due to misplacement and loosening.

## Abstract

This retrospective single-center study aimed to compare the accuracy and revision rates of pedicle screw (PS) placement using robot-guided (RG), intraoperative CT-navigated (iCT-nav), and fluoroscopy-guided (FG) techniques. Additionally, screw loosening and overall revision rates were assessed across all three methods.

Data from 237 consecutive patients who underwent PS placement using iCT-nav, FG, or RG were analyzed. Each PS was evaluated in intraoperative or postoperative CT and classified using the Gertzbein-Robbins Scale (GRS). Follow-up CT to assess fusion and screw loosening was performed at a median of 8 months (IQR = 5–17).

A total of 1352 PS were placed: 444 with RG, 667 with FG, and 241 with iCT-nav. RG showed the highest rate of GRS A screws (91.7 %) compared to iCT-nav (86.2 %) and FG (80.5 %). The iCT-nav group had the lowest revision rate due to loosening (p < 0.001), while the FG group showed the highest revision rates due to misplacement (p < 0.001) and loosening (p = 0.001). Radiation exposure (effective dose, ED) was significantly lower in the iCT group compared to the FG group.

RG PS placement demonstrates superior accuracy compared to iCT-nav and FG. Furthermore, intraoperative CT imaging significantly reduces total radiation exposure for patients.

•Robot-guided screws showed the highest accuracy in our cohort, with no postoperative revisions observed.•Screw loosening varied across techniques; smaller pedicle and screw diameters were associated with higher risk.•iCT-based approaches were linked to lower in-hospital radiation exposure than fluoroscopy.•Image-guided techniques (RG and iCT-nav) showed favorable accuracy and radiation profiles compared with FG.

Robot-guided screws showed the highest accuracy in our cohort, with no postoperative revisions observed.

Screw loosening varied across techniques; smaller pedicle and screw diameters were associated with higher risk.

iCT-based approaches were linked to lower in-hospital radiation exposure than fluoroscopy.

Image-guided techniques (RG and iCT-nav) showed favorable accuracy and radiation profiles compared with FG.