Radiographic Outcomes of Intramedullary Fixation of the Distal Fibula in Unstable Ankle Fractures

Abstract

Category: Trauma; Ankle Introduction/Purpose: Intramedullary fixation of the distal fibula in unstable ankle fractures provides an alternative treatment strategy to traditional techniques and may reduce the complication profile. While often reserved for soft-tissue protection or elderly patients, the indications for this technique continue to expand. The purpose of this study was to evaluate the radiographic outcomes of ankle fractures treated with intramedullary fixation of the distal fibula with screw or flexible fixation of the syndesmosis. Methods: A retrospective case-series was performed of patients >18 years old with unstable ankle fractures treated at a single institution. Patients were treated with intramedullary fixation of the distal fibula and screw or suture-button fixation of the syndesmosis if indicated. Radiographic parameters measured included the medial clear space, tibiofibular overlap, tibiofibular clear space, talocrural angle, and fracture displacement. Fracture pattern, comorbidities, and postoperative complications were also assessed. Results: Fourteen patients (6 males, 8 females) with torsional ankle fractures (71% SER-IV patterns) were included in the study with a mean follow-up period of 5 months. Five patients had suture-button fixation and one patient had trans-syndesmotic screw fixation of the syndesmosis. All patients had improvement in radiographic parameters following surgical stabilization. Medial clear space decreased from a mean of 5.6 +- 3.1mm to 2.8 +- 0.79mm (p<0.0001). Tibiofibular overlap increased from 0.4 +- 2.7mm to 3.0 +- 1.5mm (p<0.05). Fracture displacement of the fibula decreased from 3.5 +- 1.8mm to 0.61 +- 1mm (p<0.0001). There was no statistically significant difference between preoperative and postoperative tibiofibular clear space and talocrural angle measurements. There were no lateral wound complications, revision surgeries, or hardware complications. Conclusion: This case-series demonstrates the successful use of intramedullary fixation of distal fibula fractures in unstable ankle injuries with good radiographic and clinical outcomes. The use of an intramedullary device does not preclude trans-syndesmotic screw or suture-button fixation of concomitant syndesmotic injuries. Orthopedic surgeons can consider this treatment strategy as an alternative to traditional techniques.