Effect of deformation rate on the flexural strength of human ribs

In order to characterize the mechanical behavior of bones under various loading conditions, it is important to determine the effect of strain rate on the load carrying capacity and fracture behavior of various members of our skeletal system. In this study we tested five groups of human rib samples at five different loading rates. The ultimate stress for the two groups tested at the highest deformation rates increased compared to groups tested at the lowest deformation rates as did the elastic modulus. Ultimate strain decreased between the group loaded at 0.4 mm/s compared to the group loaded at 50 mm/s. These data show bone to be viscoelastic in nature and its mechanical properties to change with a variation in the strain rate.