# X-ray Image-Based Pose Estimation of a Joint-Encoded Spinal Surgical Positioning Arm

## TL;DR

A new spinal surgical positioning arm uses X-ray images to estimate its position, aiming to reduce radiation exposure and surgery time.

## Contribution

A novel passive spinal surgical positioning arm with X-ray image-based pose estimation is introduced.

## Key findings

- The system achieved a mean translational error of 1.08 ± 0.40 mm in positioning accuracy.
- The average setup time was 2.3 ± 0.9 minutes, and the surgical operation time was 4.2 ± 1.8 minutes.
- An average radiation dose of 0.27 ± 0.04 mGy was achieved per procedure using 6.75 ± 0.95 X-ray images.

## Abstract

Minimally invasive spinal surgery requires accurate and efficient surgical tool positioning; however, current optical or navigation-assisted systems can be costly, complex, or expose patients to increased radiation. To address these challenges, we propose and evaluate a novel passive spinal surgical positioning arm with X-ray image-based pose estimation capability. The system estimates the 6-degree-of-freedom pose of the arm using radiographic landmarks extracted from a single intraoperative X-ray image.

In our experiment, a surgeon performed single-level pedicle screw placement on three sawbones spine models. The estimated positioning accuracy achieved a mean translational error of 1.08 ± 0.40 mm. The average setup time was 2.3 ± 0.9 minutes, and the surgical operation time was 4.2 ± 1.8 minutes. Only 6.75 ± 0.95 X-ray images were required per procedure, resulting in an average radiation dose of 0.27 ± 0.04 mGy.

These results demonstrate that our system can potentially reduce radiation exposure and surgical duration while maintaining high positioning accuracy. Further clinical validation is required to confirm its effectiveness in real-world surgical settings.