Robot-assisted upper cervical spinal surgery

摘要

The fundamental for upper cervical spinal surgery is screws fixation progress, however, anatomical variations of atlantoaxial vertebrae are wide, and the region is adjacent to important organ such as spine cords, oblongata and vertebral artery, all of which make the fixation harder. Robot-assisted navigation can make up for the above shortcomings, and has the potential to more improve the screw placement accuracy. We recently designed a robot system called TiRobot, which is based on intraoperative three-dimensional images. TiRobot has three components: the planning and navigation system, optical tracking system and robotic arm system. By combining navigation and robot techniques, TiRobot can guide the screw trajectories for orthopedic surgeries. TiRobot has been used in upper cervical surgeries with the approval from the Ethics Committee. There were 7 screws inserted during the surgeries, 1 screw for posterior C1- 2 trans-articular fixation, 1 screw for anterior odontoid fixation and 5 for C1 or C2 pedicel fixation. All surgeries were smoothly performed using TiRobot. According to the post-operation CT image data, all the screw placements were sufficient because there was no perforation of the spinal canal or any unexpected malposition. According to the Gertzbein-Robbins classification, all screws fell into group A. Furthermore, there was a discrepancy between the planned and the actual placements at the entry points and the end points. The average deviation in entry point and end point were 1.21 +/- 0.45mm and 1.19 +/- 0.36mm. These safe and accurate results make TiRobot the first medical robot could be used in upper cervical spinal surgery.