The influence of laterality, sex and family history on clubfoot severity

PURPOSE: Epidemiological studies on idiopathic clubfeet have shown a typical distribution consistent across ethnic groups: bilaterality in about 50% of cases and a male to female ratio of 2:1. Whether this corresponds also to differences in severity according to laterality and sex has been poorly evaluated. As well, the correlation between family history and severity has not been previously investigated. The aim of this study was to investigate how laterality, sex and family history influence severity and treatment. METHODS: In all, 97 infants with idiopathic clubfoot (81 male, 16 female; 55 unilateral, 42 bilateral; 19 with a first or second-degree relative affected) consecutively treated with Ponseti method were prospectively enrolled. Initial severity (according to Dimeglio and Pirani scores) and treatment (number of casts and need for tenotomy) were analyzed in the different subgroups. RESULTS: Initial severity according to Pirani (p = 0.020) and Dimeglio score (p = 0.006), number of casts (p = 0.000) and tenotomy (p = 0.045) were significantly higher in bilateral than in unilateral cases. In bilateral cases, a significant correlation was found between the right and left foot of each patient in terms of initial severity, number of casts and tenotomy performed. No statistically significant difference was found according to sex and family history. CONCLUSIONS: This study has confirmed the different behaviour of bilateral cases reported by previous studies; bilateral cases are more severe and show similar features in their right and left foot. This could be the result of different pathogenic mechanisms, likely on a genetic basis. Sex and family history did not seem to influence severity. LEVEL OF EVIDENCE: Level of evidence II