Medical & Biological Engineering & Computing

, Volume 55, Issue 8, pp 1249–1260 | Cite as

Fracture characterization of human cortical bone under mode II loading using the end-notched flexure test

  • F. G. A. Silva
  • M. F. S. F. de Moura
  • N. DouradoEmail author
  • J. Xavier
  • F. A. M. Pereira
  • J. J. L. Morais
  • M. I. R. Dias
  • P. J. Lourenço
  • F. M. Judas
Original Article


Fracture characterization of human cortical bone under mode II loading was analyzed using a miniaturized version of the end-notched flexure test. A data reduction scheme based on crack equivalent concept was employed to overcome uncertainties on crack length monitoring during the test. The crack tip shear displacement was experimentally measured using digital image correlation technique to determine the cohesive law that mimics bone fracture behavior under mode II loading. The developed procedure was validated by finite element analysis using cohesive zone modeling considering a trapezoidal with bilinear softening relationship. Experimental load-displacement curves, resistance curves and crack tip shear displacement versus applied displacement were used to validate the numerical procedure. The excellent agreement observed between the numerical and experimental results reveals the appropriateness of the proposed test and procedure to characterize human cortical bone fracture under mode II loading. The proposed methodology can be viewed as a novel valuable tool to be used in parametric and methodical clinical studies regarding features (e.g., age, diseases, drugs) influencing bone shear fracture under mode II loading.


Bone Fracture characterization Mode II ENF test Cohesive zone modeling 



The authors acknowledge the Portuguese Foundation for Science and Technology (FCT) for the conceded financial support through the research project PTDC/EME-PME/119093/2010.


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Copyright information

© International Federation for Medical and Biological Engineering 2016

Authors and Affiliations

  • F. G. A. Silva
    • 1
  • M. F. S. F. de Moura
    • 2
  • N. Dourado
    • 3
    Email author
  • J. Xavier
    • 1
    • 4
  • F. A. M. Pereira
    • 2
    • 4
  • J. J. L. Morais
    • 4
  • M. I. R. Dias
    • 4
  • P. J. Lourenço
    • 5
  • F. M. Judas
    • 5
  1. 1.INEGI - Instituto de Ciência e Inovação em Engenharia Mecânica e Engenharia IndustrialPortoPortugal
  2. 2.Departamento de Engenharia MecânicaFaculdade de Engenharia da Universidade do PortoPortoPortugal
  3. 3.CMEMS-UMinho, Departamento de Engenharia MecânicaUniversidade do MinhoGuimarãesPortugal
  4. 4.Centre for the Research and Technology of Agro-Environmental and Biological Sciences, CITABUniversity of Trás-os-Montes and Alto Douro, UTADVila RealPortugal
  5. 5.Banco de Tecidos Ósseos do Centro Hospitalar e Universitário de Coimbra - CHUC, EPEFaculdade de Medicina da Universidade de CoimbraCoimbraPortugal

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