Safety and accuracy of robot-assisted pedicle screw fixation: a randomized controlled trial

Accurate pedicle screw placement is essential yet challenging in spinal surgery. This trial evaluated whether a robotic system with biplane fluoroscopic positioning could improve accuracy, efficiency, and safety compared to conventional fluoroscopy-guided techniques.

This multicenter, parallel-group, randomized trial was conducted at three hospitals. A total of 70 patients requiring pedicle screw fixation were randomly assigned (1:1) to either the robot-assisted group (RG) or the conventional fluoroscopy-guided group (CG). In the RG, a robotic navigation system assisted in planning and localizing the guide pin entry point and trajectory, based on a biplane algorithm that integrated anteroposterior and lateral fluoroscopic images with optical tracking data to achieve real-time spatial registration. This biplane positioning technique was derived from the principles of the Dual Fluoroscopic Imaging System (DFIS). In the CG, guide pin placement was performed under conventional fluoroscopic guidance. The primary outcome was the deviation of guide pin placement. Secondary outcomes included the cumulative number of exposures, total radiation dose, operative time, average time to establish a single channel, and number of channel adjustments.

The mean deviation of guide pin placement in the RG was significantly smaller than that in the CG (0.86 ± 0.57 mm vs. 2.55 ± 1.88 mm, P<0.001). The RG also had significantly fewer cumulative number of exposures (4.56 ± 1.70 vs. 13.38 ± 19.01, P = 0.003) and lower total radiation doses (7.35 ± 3.33 μSv vs. 30.28 ± 97.41 μSv, P = 0.024). The operative time was similar between the groups (245.03 ± 67.06 min vs. 215.18 ± 83.08 min, P = 0.083). The number of channel adjustments was significantly lower in the RG (0.06 ± 0.29 vs. 0.28 ± 0.90, P = 0.014). There were no significant differences in the incidence of adverse events between the two groups.

The robotic system with biplane fluoroscopic positioning improved guide pin accuracy and reduced radiation exposure, indicating its potential to enhance precision and safety in spinal surgery.