Surgical Outcomes of Posterior to Anterior Screw Fixation in Open Reduction and Internal Fixation of Posterior Malleolus Fractures

Research Type: Level 4 – Case series Introduction/Purpose: Up to 50% of operatively treated ankle fractures involve the posterior malleolus. Biomechanical studies suggest that posterior-to-anterior screw fixation provides superior stability compared to anterior-to-posterior fixation. However, data on clinical outcomes for this technique remains limited. This study evaluates postoperative outcomes in patients with AO/OTA 44B3 fractures treated with posterior to anterior screw fixation of Volkmann's fragment. Methods: In our series, fixation of the posterior malleolus was performed by advancing a Kirschner wire from anteromedial to posterolateral exiting lateral to the Achilles tendon. A cannulated screw was then advanced from posterior to anterior across the posterior malleolus fracture to achieve stable fixation. We performed a retrospective review of medical records for patients with AO/OTA 44B3 fractures who underwent posterior-to-anterior screw fixation of the posterior malleolus. Eligible patients were identified through an institutional database, and demographic, clinical, and surgical outcome data were collected. Outcomes of interest included time to union, infection rate, incidence of nerve injury, rate of nonunion and malunion, and reintervention rates. A descriptive statistical analysis was performed for continuous variables and frequency distributions for categorical variables. Results: A total of 93 patients were included. The mean age was 61.4 years (SD: 19.5), and 75.3% (n = 70) were female. The mean time to union was 131 days (SD: 64.1). The overall complication rate was 8.82% (n = 14), with infections occurring in 2.94% (n = 3) of cases and sural nerve injury in 0.98% (n = 1). Reintervention was required in 5.88% (n = 6), primarily due to painful hardware, none of which were related to the posterior malleolus screw. Non-union or malunion occurred in 3.9% (n = 6) of patients and delayed union occurred in 10.7% (n=10). Conclusion: Posterior to anterior screw fixation is a viable and safe method for open reduction and internal fixation of posterior malleolus fractures. Further comparative studies are needed to validate its efficacy relative to other fixation methods.