Robot-assisted sacroiliac screw fixation for tile type C posterior pelvic ring injuries: a comparative study

To compare the clinical efficacy and safety of robot-assisted versus conventional fluoroscopy-guided percutaneous sacroiliac screw fixation for Tile type C posterior pelvic ring injuries.

A retrospective analysis was conducted on 60 patients with Tile type C posterior pelvic ring injuries treated at our institution from January 2021 to December 2023. Patients were stratified into two groups based on surgical technique: a robot-assisted group (n = 31, TiRobot-assisted percutaneous sacroiliac screw fixation) and a conventional group (n = 29, C-arm fluoroscopy-guided percutaneous sacroiliac screw fixation). Group allocation reflected the surgical pathway available during the study period rather than randomisation. The following parameters were compared between groups: operative time, intraoperative fluoroscopy frequency, intraoperative blood loss, screw placement accuracy, number of guide-wire adjustments, fracture healing time, complications, and Majeed scores at final follow-up.

All patients completed 12-24 months of follow-up (mean 15.6 months). No significant difference in operative time was observed between the robot-assisted group (78.5 ± 15.2 min) and the conventional group (82.3 ± 18.6 min) (P > 0.05). The robot-assisted group demonstrated significantly fewer intraoperative fluoroscopy exposures (8.2 ± 2.1 vs. 18.6 ± 4.5, P < 0.001), fewer guide-wire adjustments (1.3 ± 0.6 vs. 4.2 ± 1.8, P < 0.001), and less intraoperative blood loss (45.2 ± 12.8 mL vs. 68.5 ± 18.3 mL, P < 0.001). The excellent-and-good screw placement rate was 97.96% (48/49) in the robot-assisted group versus 86.36% (38/44) in the conventional group (P = 0.042). No significant difference was found in fracture healing time. Majeed functional scores at final follow-up were higher in the robot-assisted group (85.6 ± 8.2) than in the conventional group (81.2 ± 9.5) (P = 0.049). No severe complications occurred in the robot-assisted group, whereas one case of L5 nerve-root irritation associated with screw malposition occurred in the conventional group.

For Tile type C posterior pelvic ring injuries, robot-assisted percutaneous sacroiliac screw fixation was associated with higher screw placement accuracy, lower intraoperative radiation exposure, fewer guide-wire adjustments, reduced blood loss, and favourable early functional outcomes compared with conventional fluoroscopy-guided fixation. These findings, derived from a single-centre retrospective cohort, should be interpreted as hypothesis-generating and warrant confirmation in prospective multicentre studies.