Abstract: OBJECTIVE: Percutaneous sacroiliac screw internal fixation has become the main surgical procedure for the treatment of posterior pelvic ring fractures; however, the unassisted closure operation requires high operator experience and repeated fluoroscopy increases the radiation hazard for patients and medical personnel. This article compares the clinical efficacy of robot-assisted versus unassisted percutaneous sacroiliac screw placement for posterior pelvic ring fractures by meta-analysis.
METHODS: Computer searches of CNKI, WanFang, VIP, CBM, PubMed, Embase, Cochrane Library and ClinicalTrials.gov were conducted from the time of database inception to December 2022. The literature on the clinical efficacy of robot-assisted versus freehand percutaneous sacroiliac screw placement in the treatment of posterior pelvic ring fractures was collected in and outside China. The data were independently screened and extracted by two investigators according to the inclusion and exclusion criteria, respectively. The quality of randomized controlled trials was evaluated using Cochrane risk assessment criteria. The quality of included cohort studies was assessed using the Newcastle-Ottawa Scale. Meta-analysis was performed using RevMan 5.4 software for inclusion metrics. Outcome metrics included operative time, intraoperative bleeding, fluoroscopy time, fluoroscopy frequency, number of holes drilled, Majeed postoperative function score, the excellent and good rates of Matta fracture reduction, the excellent and good rates of Gras screw position, fracture healing time and complications. 
RESULTS: (1) A total of 13 publications were included, 2 were randomized controlled trials both referring to randomized methods, 11 non-randomized controlled studies were evaluated for quality of literature according to the Newcastle-Ottawa Scale, 1 scored 8, 9 scored 7; and 1 scored 6; the quality of literature was good. A total of 748 patients were included, including 430 in the robot-assisted group and 318 in the freehand group. (2) The results of the meta-analysis showed that the operative time (MD=-28.30, 95%CI:-40.20 to -16.40), intraoperative bleeding (MD=-6.36, 95%CI:-10.06 to -2.66), intraoperative fluoroscopy time (MD=-12.13, 95%CI:-19.54 to -4.72), intraoperative fluoroscopy frequency (MD=-17.39, 95%CI:-29.00 to -5.78), number of intraoperative needle drillings (SMD=-9.50, 95%CI:-14.27 to -4.73) and the excellent and good rates of Gras screw position (OR=8.65, 95%Cl:3.26-22.92) in the robot-assisted group were significantly better than those in the freehand group (P < 0.05). (3) In the robot-assisted group, the overall postoperative complication rate was significantly reduced (OR=0.10, 95%Cl: 0.02-0.48, P < 0.05). (4) No significant difference was detected in fracture healing time (MD=-0.08, 95%CI:-0.21,0.06), the excellent and good rates of Matta fracture repositioning rate (OR=2.06, 95%Cl: 0.97-4.39), and Majeed functional score (MD=0.91, 95%CI: -0.31-2.13) between both groups (P > 0.05). 
CONCLUSION: Compared with freehand sacroiliac joint nailing, robotic assistance shortens the operative time, reduces intraoperative bleeding, decreases radiation damage to patients and medical staff, improves the excellent and good rate of screw position, and reduces the overall incidence of postoperative complications in patients, but there was no significant improvement in fracture reduction quality, fracture healing time, and postoperative function. In the future, more large-sample, multicenter, and high-quality randomized controlled trials are still needed to verify.

Key words: pelvis, fracture, posterior pelvic ring, robotics, robotic surgery, sacroiliac joint screw, screw, meta-analysis