Effect of micro-morphology of cortical bone tissue on fracture toughness and crack propagation

Specific features of crack propagation in human cortical bone depend on many factors; bone micro-morphology is one of the main features. A bone compact-tension simulation model with zero-thickness cohesive element is employed in this study to investigate the effect of micro-morphology of cortical bone on fracture toughness and crack propagation. Various groups of bone sample – from young, senior, diseased and treated patients – were studied. It was found that the young group has the best performance in terms of fracture resistance, with the initiation fracture toughness (K0) and slope of 1.45 MPa(m)1/2 and 1.16 MPa(m)1/2/mm, respectively. The cracks in this group propagate mostly along the cement line to protect osteons from crack penetration.