Mechanical properties of different combinations of flexible nails in a model of a pediatric femoral fracture.

Flexible nailing of pediatric femoral shaft fractures is based on the principle of using two C-shaped nails to create six points of fixation. However, clinical studies using various nail combinations demonstrate similar outcomes. This study aimed to compare the mechanical properties of different nail combinations by testing them in a model of a child's midshaft femoral fracture. The two C-shaped nails were compared with two straight nails and with paired S- and C-shaped nails. The constructs were tested in four-point bending and torsion. Graphs of the data were produced, from which the bending and torsional stiffness of the constructs was calculated. The results showed that there was no significant difference between the mechanical properties of the three different constructs. The conclusion is that any of the tested nail combinations can be used to treat a midshaft fracture of the femur in a child.