Comparative retrospective study of triangular osteosynthesis with and without robotic assistance for unilateral unstable sacral fractures combined with lumbosacral junction injuries

Background To compare the clinical efficacy of unilateral unstable sacral fractures (USFs) involving the lumbosacral region treated with and without robot-aided triangular osteosynthesis (TOS). Methods Patients of the unilateral USF combined with the ipsilateral lumbosacral junction injury (LSJI) treated with TOS were retrospectively analyzed and divided into two groups: the robot group (TOS with robotic assistance) and the conventional group (TOS with open procedure). Screw placement was assessed using the modified Gras criterion. Patients were followed up with routine visits for clinical and radiographic examinations. At the final follow-up, clinical outcomes were recorded and scored using the Majeed scoring system. Results Eleven patients in the robot group and seventeen patients in the conventional group were recruited into this study. Significant differences in surgical bleeding (P < 0.001) and fluoroscopy time (P = 0.002) were noted between the two groups. Operation time (P = 0.027) and fracture healing time (P = 0.041) was shorter in the robot group. There was no difference in postoperative residual displacement between the two groups (P = 0.971). According to the modified Gras criterion, the percentages of grade I for sacroiliac screws in the two groups were 90.9% (10/11) and 70.6% (12/17), and for pedicle screws were 100% (11/11) and 100% (17/17), respectively. The rate of incision-related complications was 0% (0/11) in the robot group and 11.8% (2/17) in the conventional group. Statistical differences were shown on the Majeed criterion (P = 0.039), with higher scores in the robot group. Conclusion TOS with robotic assistance for the treatment of unilateral USFs combined with ipsilateral LSJIs is safe and feasible, with the advantages of less radiation exposure and fewer incision-related complications.