Transiliac–Transsacral Screw Provides Good Outcomes for Stabilizing Unstable Fragility Fracture of the Pelvis: A Retrospective Case Series

(1) Background: Fragility fractures of the pelvis (FFP) in elderly patients pose significant clinical challenges due to osteoporosis and associated morbidity. Transiliac–transsacral (TITS) screw fixation offers biomechanical advantages for stabilizing unstable posterior pelvic ring injuries, yet clinical outcomes remain underreported. We aim to report radiographic and clinical outcomes of TITS fixation for posterior pelvic ring injuries in FFP. (2) Methods: We conducted a retrospective review of 22 elderly female patients (mean age 79.0 ± 7.9 years) who underwent TITS screw fixation for unstable posterior pelvic ring fragility fractures between 2019 and 2024. Perioperative, radiographic, and functional outcomes were analyzed. (3) Results: Median operative time was 74 min (IQR 55–90 min), with minimal blood loss (median 5 mL). No intraoperative neurovascular injuries occurred. Median hospital stay was 7 days (IQR 5–10 days). At a mean follow-up of 6 months, 81.8% of patients maintained excellent or good reduction. Screw loosening was observed in 18.2% of cases, with only one (4.5%) requiring revision. Median VAS scores (range 0–10) decreased significantly from 5 preoperatively to 2 at discharge (p < 0.001). By discharge, 59.1% of patients were able to ambulate with assistance. (4) Conclusion: TITS screw fixation is a safe and feasible option for stabilizing unstable FFP in elderly, osteoporotic patients. It provides reliable mechanical stability, promotes early mobilization, and is associated with a short hospital stay and low complication rates.