Forty-seven children with non-reduced diaphyseal both-bones forearm fractures were randomized to receive either above-elbow cast (AEC) (n=23) or early conversion to below-elbow cast (BEC) (n=24). The primary outcome of interest was the limitation of forearm rotation. Secondary outcomes of interest included loss of flexion and extension of the elbow and wrist, patient-reported outcomes measures, grip strength ratio, and radiographic assessment. Outcomes were assessed up to 7.5 years. Overall, the results of the study revealed that forearm rotation improved over time in both groups without significant differences between them. The long-term follow-up confirms that early conversion to BEC is as effective as AEC, suggesting that growth potential plays a significant role in recovery​​.