Category: Trauma Introduction/Purpose: The current gold-standard for unstable distal fibula fractures is plate and screw fixation; however, intramedullary distal fibular fixation is becoming more commonplace. Although surgeons may consider this technique only for patients requiring extra soft tissue protection, recent studies are showing that it is a safe and effective technique for maintaining adequate reduction and promoting proper fracture healing in a wide-variety of ankle fractures. As newer techniques and equipment are developed, it is important to continue with analyzation of patient outcomes. Our study evaluates a intramedullary device that contains a unique proximal locking mechanism that deploys fins against the inner cortex to help maintain fracture length and control rotation. To our knowledge, no other study in the literature has evaluated this technique for distal fibula fractures. Methods: A retrospective case-series was conducted on all patients >18-years old with unstable ankle fractures treated with the same intramedullary distal fibular fixation, that contained the unique proximal locking system. Surgeries were performed at a single institution by a single surgeon between September 2015 and June 2018. Patient imaging was carefully assessed for quality of reduction using previously established guidelines classifying reductions as “good”, ”fair”, or “poor”. Patient charts were also assessed for comorbidities, initial fracture classification, postoperative complications, and need for additional surgery. Results: Forty-one patients were included in the study. Twenty-five patients were female and 16 patients were male. Average age was 52. Average follow-up was 10.0 months. Eleven fractures were bimalleolar (27%), eight were isolated distal fibula fractures (20%), eight were bimalleolar-equivalent fractures (20%), nine were trimalleolar fractures (22%), and five were pilon fractures (12%). Seventy-one percent were Weber B and 29% were Weber C. Based on the classification system, 37 fracture reductions (90%) were classified as ”good”, four were “fair” (10%), and no reductions were ”poor”. There were no instances of hardware failure, loss of reduction, or nonunion. One patient had a superficial wound infection, one patient had a deep wound infection, five patients require painful hardware removal, and one patient had a delayed union. Conclusion: This large case-series is the first study, to our knowledge, in the Foot and Ankle literature to evaluate this specific intramedullary distal fibular fixation system that contains a unique-proximal fixation mechanism within the canal itself. This technique was used for a variety of unstable ankle fractures and was shown to be both safe and effective, and will help guide future prospective studies comparing outcomes with the gold-standard plate and screw fixation.