Comparison of Dimeglio and Pirani score in predicting number of casts and need for tenotomy in clubfoot correction using the Ponseti method

PURPOSE: The Dimeglio and the Pirani scores are largely used to rate clubfoot at presentation and monitor correction. To date, the accuracy of these scores in predicting appropriate treatment is controversial. The aim of this study was to investigate the accuracy of Dimeglio and Pirani scores in predicting the number of casts and the need for tenotomy in clubfoot correction using the Ponseti method.

METHODS: Ninety-one consecutive feet (54 patients; mean age at presentation: 28 ± 15 days) undergoing clubfoot correction using the Ponseti method were prospectively followed from first casting to correction. All feet were scored according to the Dimeglio and Pirani score. The relationships between the two scores, the number of casts and the need for tenotomy were analysed.

RESULTS: Initial correction was achieved in all feet. Both Dimeglio (r = .73; p value < .0005) and Pirani scores (r = .56; p value < .000) showed good association with the number of casts. Multiple linear regression showed a high collinearity of the two scores but a more significant contribution of the Dimeglio score. Among subcomponents, hindfoot score, midfoot score, varus and muscular abnormality were independent predictors of the number of casts. Both Dimeglio and Pirani scores were significantly associated with the need for tenotomy (p value = .0000), and odds ratios and cut-off points were calculated. The receiving operator curve (ROC) analysis showed slightly better performance of the Dimeglio in comparison with the Pirani score in predicting the need for tenotomy, but the difference between the two areas under the curve (AUC) was not significant (p = .48).

CONCLUSIONS: A quite accurate prediction of the number of casts and the need for tenotomy can be performed in most cases. The Dimeglio score showed slightly better accuracy in predicting both steps of Ponseti treatment.