The use of flexible intramedullary nailing, allowing micro movement at the fracture site, results in excellent outcomes regardless of the number of nails used. We undertook analysis of the outcomes of flexible nailing with reference to the number of nails used. Twenty patients with diaphyseal femur fracture aged 5-15 years were treated with retrograde flexible intramedullary nailing. The number of nails varied from single to multiple. The results were analysed with regard to the number of nails used. The mean patient age was 7.9 years; patients were followed up for a mean duration of 13.2 months. Those with two and three nails had similar results. A minimum of two flexible nails is needed for optimal fixation in paediatric femur shaft fractures. Also, limiting the number of implants to two is cost effective, decreases operative time, reduces radiation exposure and offers equal results to that of three nails.