PSI - Issue 68

P. Langourani-Kosteletou et al. / Procedia Structural Integrity 68 (2025) 112–118 P. Langourani-Kosteletou et al. / Structural Integrity Procedia 00 (2025) 000–000

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while those fixed with 32 mm threaded screws required a higher torque limit of 2.5 Nm to be adequately tightened. Consequently, different interfragmentary compression forces may have been induced between the fixed sawbone blocks in the two groups. 5. Conclusion- Future Perspectives In the present study, the effect of the thread length in fixation under shear loading was examined, and the main conclusion drawn was that constructs fixed with long-threaded screws exhibited statistically significantly greater stiffness, proportionality limit, and yield load than those fixed with short-threaded screws. These findings are consistent with previous research in the literature. Consequently, the length of thread engagement is an essential feature of screw design that may affect not only the holding power of screws but also the resistance of fixation to shear loading. The present study can serve as a foundation for further examination of various fixation parameters under shear loading, a relatively unexplored area of investigation. In addition, researchers can investigate whether there is a correlation between the compression produced by different screw thread lengths and construct failure under shear loading. Finally, the experimental data gathered may allow the validation and calibration of numerical models simulating the specific fixation problem, aiming to explore the role of the various parameters affecting the response of the fixation techniques. References Asnis, S.E., Ernberg, J.J., Bostrom, M.P., Wright, T.M., Harrington, R.M., Tencer, A., Peterson, M., 1996. Cancellous bone screw thread design and holding power. Journal of Orthopaedic Trauma, 10(7), 462-469. ASTM International-F1839–08, 2021. Standard specification for rigid polyurethane foam for use as a standard material for testing orthopaedic devices and instruments [Online]. Available at: https://cdn.standards.iteh.ai/samples/108298/c6b67e9c1a2441f98b912d1716daba13/ASTM-F 1839-08-2021-.pdf (Accessed:13 April 2024). Benoit, D., Franck Le Navéaux, A., Posch, A., 2023. Orthopedic screw pullout prediction: validation of a virtual mechanical test for the prediction of screw pullout forces in Sawbones polyurethane foam in accordance to ASTM F543 standard. White Paper, [online].Available at: https://numalogics.com/wpcontent/uploads/2023/05/White_Paper_Orthopedic_Screw_Pullout_Prediction.pdf (Accessed: 20 May 2024) Chapman, J.R. Harrington, R.M., Lee, K.M., Anderson, P.A., Tencer, A.F., Kowalski, D., 1996. Factors affecting the pullout strength of cancellous bone screws. Journal of Biomechanical Engineering, 118(3), 391-398. Chatzistergos P., 2010. Biomechanics of the stabilized spinal column: study of the lumbar spinal implants for the evaluation-validation of their biomechanical efficiency. National Archive of PhD Theses [online]. 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