The aim of this study was to assess the usefulness of currently available indices for casting in distal radius fractures in children and to identify risk factors associated with displacement. A cohort of 14 patients with redisplacement was compared with a cohort of 41 patients with maintenance of reduction. A significant difference (<0.008) was observed in the three-point index, the degree of comminution (<0.01) and the quality of the initial reduction (<0.003). We recommend careful identification of high-risk factors and appropriate stabilization for potentially unstable fractures at first treatment. Assessment of the three-point index is recommended for judging the moulding technique.