Langenskiöld classification of tibia vara: an assessment of interobserver variability.

Six pediatric orthopaedic specialists and six senior orthopaedic residents independently classified 60 radiographs of infantile tibia vara according to the six-stage Langenskiöld classification. Correlation coefficients and percentage agreement were similar in both groups. Interobserver agreement was good for early and late stages, but was poor for intermediate stages. We caution clinicians that small but frequent discrepancies in radiographic staging impart a dubious prognostic value to the Langenskiöld classification.