Diaphyseal and metaphyseal fractures in children are frequently treated with the flexible intramedullary nailing (FIN) method. The aim of this study was to record postoperative complications and outcome in consecutive fracture patients treated with the new precurved tip and shaft nails and dedicated ergonomic instrumentation.

We report the analysis of 100 consecutive fractures followed up for a minimum of 6 months. Ninety-seven children were included, comprising 77 shaft and 23 metaphyseal fractures. Demographic data, duration of surgery, nail and medullary canal diameter, date of nail removal, clinical assessment, follow-up radiographs and all complications were recorded.

Mean age was 9.7 years, and mean body weight 35.1kg. Twenty-one fractures had associated lesions. Mean duration of surgery was 42.4minutes. Nail removal was at a mean 6.1 months. Twelve percent of patients had complications, with six insufficient reductions, one delayed union, one non-union, one iterative fracture, and three skin impingements. Unexpected surgical revision was required in seven cases. At follow-up, only one patient showed functional impairment, with 20° pronation loss, and three showed more than 10° axial deviation on X-ray.

The low rate of skin impingement compared with the literature may be due to the new dedicated instruments. We believe that other complications can be avoided if one follows the FIN principles, avoiding weak assembly due to an insufficient nail/medullary canal diameter ratio, which is a limiting factor for indications in adolescents. The surgeons reported that precurved shaft nails facilitated the FIN procedure, although this subjective judgment may be due simply to the novelty of the nails.

Level IV. Retrospective study.