Reliability of Fracture Classifications in Surgically Treated Simple Ankle Fractures

Background Reliable fracture classification is essential for communication, treatment planning, and research. Several systems classify ankle fractures, but their reproducibility remains debated. We evaluated inter- and intrarater reliability and agreement of the Weber, Lauge-Hansen, and AO/OTA classifications among orthopedic and radiology clinicians. Methods We retrospectively identified 265 surgically treated ankle fractures at Randers Regional Hospital, Denmark, from February 2020 to December 2024. Four observers (orthopedic resident, orthopedic consultant, radiology intern, radiology resident) independently classified preoperative radiographs. After three months, they reassessed 50 randomly selected cases. Reliability was quantified using Gwet's agreement coefficient (AC) with 95% confidence intervals and percent agreement. Results The Weber classification demonstrated very good interrater reliability (AC 0.90; 91% agreement). Lauge-Hansen (AC 0.70; 72%) and AO/OTA (AC 0.66; 69%) showed good agreement. Intrarater reliability was highest for Weber across all observers (AC 0.82-0.89).  Conclusion The Weber classification provides superior reliability compared with Lauge-Hansen and AO/OTA when applied to plain radiographs of surgically treated ankle fractures.