Reproducibility of the stability-based classification for ankle fractures

BACKGROUND: Classification of ankle fracture is important when deciding for operative or conservative treatment. This study rates the reproducibility of ankle stability assessment and compares it with the classification by Lauge-Hansen and Arbeitsgemeinschaft für Osteosyntesefragen (AO) in adult patients with primary ankle fractures.

METHODS: A total of 496 consecutive ankle fractures were included, and the X-ray images were reviewed 2 times by 2 medical students, 2 residents, and 1 consultant in orthopedic traumatology. The raters were blinded to each other and to their own results. Unweighted Kappa statistics were used to assess reproducibility.

RESULTS: Overall mean (95% CI) interrater Kappa results were 0.65 (0.64; 0.68) for Lauge-Hansen, 0.62 (0.60; 0.63) for AO and 0.61 (0.57; 0.62) for the stability assessment. The intrarater results ranged from a mean Kappa of 0.64-0.80 for the medical students, 0.65-0.81 for the residents and 0.82-0.84 for the consultant.

CONCLUSION: The stability assessment has substantial to almost-perfect agreement which is comparable to the Lauge-Hansen and AO classifications.