How cross screw length influences the stiffness of intramedullary nail systems
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Abstract
Fractures of long bones are commonly treated with intramedullary (IM) nails and they have been shown to have a very high success rate. Recently we have concerns with the use of the newer IM nailing systems, that uses longer cross screws, which have been developed with variation in implant designs. We believe that the newer implants provide less fracture stability, due to decreased stiffness of the IM nailing system. The aim of this study was to biomechanically determine the influence of the length of cross screw on the stiffness of the IM nailing system, using a composite model. Our test results confirmed our suspicion that the newer IM nailing system using longer cross screw-length is less stiff than traditional nailing systems using shorter cross screw length, during axial loading.
- Wolinsky, P.R., McCarty, E., Shyr, Y. and Johnson, K. (1999) Reamed intramedullary nailing of the femur: 551 cases. Journal of Trauma-Injury Infection & Critical Care, 46, 392-399.
- Wiss, D.A. and Stetson, W.B. (1995) Unstable fractures of the tibia treated with a reamed intramedullary inter-locking nail. Clinical Orthopaedics & Related Research, 56-63.
- Rommens, P.M, Verbruggen, J. and Broos, P.L. (1995) Retrograde locked nailing of humeral shaft fractures. A review of 39 patients. see comment. Journal of Bone & Joint Surgery - British Volume, 77, 84-89.
- Bick, E.M. (1968) The intramedullary nailing of frac-tures by G. Kuntscher. Translation of article in Archiv fur Klinische Chirurgie. Clinical Orthopaedics & Related Research, 60, 5-12.
- Schatzker, J. (1998) Fractures of the distal femur revis-ited. Clinical Orthopaedics & Related Research, 43-56.
- Brumback, R.J., Toal, T.R., Murphy-Zane, M.S., Novak, V.P. and Belkoff, S.M. (1999) Immediate weight-bearing after treatment of a comminuted fracture of the femoral shaft with a statically locked intramedullary nail. Jour-nal of Bone & Joint Surgery – Am, 81, 1538-1544.
- Hente, R., Fuchtmeier, B., Schlegel, U., Ernstberger, A. and Perren, S.M. (2004) The influence of cyclic com-pression and distraction on the healing of experimental tibial fracture. Journal of Orthopaedic Research, 22, 709-715
- Taylor, S.J., Walker, P.S., Perry, J.S., Cannon, S.R. and Woledge, R. (1998) The forces in the distal femur and the knee during walking and other activities measured by telemetry. J.Arthroplasty, 13, 428-437.
- Schandelmaier, P., Farouk, O., Krettek, C., Reimers, N., Mannss, J. and Tscherne, H. (2000) Biomechanics of femoral interlocking nails. Injury, 31, 437-443.
- Henley, M.B., Meier, M. and Tencer, A.F. (1993) Influ-ences of some design parameters on the biomechanics of the unreamed tibial intramedullary nail. J Orthop Trauma, 7, 311-319.