Robot-assisted treatment of unstable pelvic fractures with a percutaneous iliac lumbar double rod fixation combined with a percutaneous pelvic anterior ring INFIX fixation

Objective To investigate the clinical effect of robot-assisted treatment of unstable pelvic fractures through a percutaneous iliac lumbar double rod fixation combined with a percutaneous pelvic anterior ring INFIX (internal fixator) fixation. Methods This was a retrospective analysis of 17 cases of unstable anterior and posterior pelvic ring fractures treated between April 2016 and October 2018 by the third Ti-robot system produced in China. The posterior ring was supported with an iliac lumbar double rod fixation and the anterior ring with an INFIX fixation. Operation time and peri-operative bleeding were recorded. The reduction of pelvic fracture displacement was evaluated by Matta score, the post-operative results were evaluated according to Majeed score, and the complications were recorded. Results Twelve males and five females, aged 21-71 years (mean 40.1 +/- 3.8 years) were followed up for three to 12 months, (median 6.7 months). Tile typing showed seven B1 type, two B2 type, and eight C1 type cases. Operation time was 90-160 minutes (mean 112.9 +/- 16.8 minutes), bleeding was 80-150 mL (mean 105.9 +/- 20.6 mL). X-ray three to five days after operation was evaluated by Matta score as excellent in 15 and good in two cases. Majeed score at last follow-up was 85-98 points, excellent in 17 cases. Two cases of lower extremity deep vein thrombosis received an inferior vena cava filter. The filters were removed after two weeks. One case showed incision fat liquefaction healing and the wound healed three weeks after surgery. Conclusion Orthopedic robot-assisted treatment of unstable pelvic fractures by a percutaneous iliac lumbar double rod fixation and a percutaneous pelvic anterior ring INFIX fixator was minimally invasive and feasible. A prospective study is needed.