Treatment of Unstable Sacral Fractures with Robotically-aided Minimally Invasive Triangular Fixation

Objective: The treatment of unstable sacral fractures is huge challenge to surgeons. Robotically-aided minimally invasive triangular fixation (RoboTFX) is the most advanced technique up to now. This study is to evaluate the clinical outcomes of unstable sacral fractures treated with RoboTFX. Methods: From March 2017 to October 2021, 48 consecutive patients with unstable sacral fractures were included in the study. All patients received surgical treatment with triangular fixation (TFX). Patients were divided into four groups according to the number of fractures (uni- or bilateral) and surgical method employed (RoboTFX or traditional open TFX). Between these four groups, clinical data on operation time, intraoperative bleeding, intraoperative fluoroscopy time, infection rate, fracture healing rates, insertion accuracy, Majeed pelvic outcome score, Mears' criterion, and Gibbons score were compared. Quantitative data were expressed as mean +/- standard deviation and compared using Student's t-test. Categorical variable were compared using the Pearson's chi(2) test. Results: Comparing unilateral RoboTFX versus open TFX, neither fracture healing rate, infection rate, Majeed pelvic outcome score, Mears' radiological evaluation criterion, nor Gibbons score of the two groups were statistically significantly different (p > 0.05). However, operation time, intraoperative bleeding, intraoperative fluoroscopy time, and insertion accuracy in the RoboTFX group were all significantly better than those of the traditional open group (p < 0.05). Likewise, operation time, intraoperative bleeding, intraoperative fluoroscopy time, and accuracy of fixation insertion of the bilateral RoboTFX group were significantly better than those of the bilateral open group (p < 0.05). Meanwhile infection rate, fracture healing rate, Majeed score, Mears' criterion, and Gibbons score of two groups were not significantly different (p > 0.05). Conclusion: RoboTFX has the advantages of less operation time, less intraoperative bleeding and fluoroscopy, more accurate fixation insertion, and a higher healing rate compared to traditional open methods in the treatment of unstable sacral fractures. However, RoboTFX requires a few critical considerations, and the indications of its operation should be strictly evaluated.