Minimally Invasive “Crab-Shaped Fixation” for Treating Patients with Fragility Fractures of the Pelvis

INTRODUCTION: In the aging society, fragility fracture of the pelvis (FFP) has become a problem. Although strong and minimally invasive fixation is required in FFP surgery, reports on relevant surgical results are scarce. Crab-shaped fixation (CSF) is a spinopelvic fixation that involves reconstruction of the posterior pelvic ring using spinal instrumentation. This study aimed to evaluate the walking ability and perioperative complications of patients who underwent CSF for FFP. METHODS: We included patients diagnosed with unstable FFPs, including sacral fracture, who required hospitalization. Demographic data, such as age, sex, bone mineral density, and Rommens classification, were evaluated. Surgical findings included estimated blood loss, operation time, and perioperative complications. The improvement in postoperative walking ability was evaluated based on the length of the postoperative period before the initiation of walker training and whether walking aids were required at 6 months post-surgery, compared with those who received conservative treatment for FFP. RESULTS: Our study included 6 cases that received CSF and 16 cases that received conservative treatment, in which all were females and presented with sacral fractures. The average age of the surgical patients, the operation time, and the estimated blood loss were 79.5±14.7 years, 180.7±28.7 min, and 124.2±29.4 mL, respectively. The average length of the postoperative period prior to the initiation of walker training was 10.8±12.3 days, which was significantly shorter than that of conservative treatment. With regard to perioperative complications, poor reduction of fracture dislocation was observed in one case as well as surgical site infection in another case, but the walking ability improved in all cases. CONCLUSIONS: We evaluated the results of the posterior pelvic ring reconstruction with CSF for patients with vertically unstable FFPs, including sacral fractures. CSF is minimally invasive and would be useful as it allowed walker training during the early postoperative period, which improved patients' walking ability even during the in situ pelvic ring reconstruction.