Figure 1.

Schematic of mechanical test plot from three-point bending test of dog rib. Load versus deformation data from tests are converted to stress and strain, respectively, using standard equations (see methods for equations). In these tests, the yield stress and ultimate stress are nearly identical, while there is a considerable amount of displacement (strain) between these points and the point of fracture. In the current study, toughness (the area under the stress/strain curve) was quantified fracture (total area under the curve). We also separated the area under the curve into pre-yield toughness (area of the curve to ultimate stress, lightly shaded region) and post-yield toughness (area under the curve between ultimate stress and fracture, darkly shaded region). Previous analyses by Komatsubara [6] assessed toughness only to the point of ultimate stress.