title: Derby intramedullary nail--a biomechanical comparison.
abstract: This paper describes the design and function of the Derby intramedullary nail and its biomechanical testing, comparing it with the K nail and reamed unfractured femurs. The Derby nail is designed to transmit torsional loads and apply compression to the fracture site using a sliding proximal collar and distal extendable 'wings'. Femurs fixed with Derby, K and Zickel nails and AO plates were tested in torsion and the rotation and torsional load at failure recorded and compared with unfractured control femurs. The results show that the strength of the Derby nail in torsion is approximately equal to 4 times and the energy to failure 2.3 times that of the K nail.
mesh_terms: D001696:Biomechanical Phenomena; D001698:Biomedical Engineering; D001858:Bone Nails; D005264:Femoral Fractures / Q000601:surgery; D005594:Fracture Fixation, Intramedullary / Q000295:instrumentation*; D006801:Humans