ALT Representative mechanical behavior of two commonly used animal model tendons under uniaxial tension (superficial digital flexor tendon, SDFT,25 tail fascicle, TF26). To describe the material properties, stress (σ) is plotted against strain (ε), after normalization according to tissue dimensions. The curve is annotated to show important behaviors that are interpreted in Table 1. A–B represent the toe region and B–E represent the elastic region of the loading curve. The stress at E represents the yield point, or the onset of “failure in continuity.” The maximum stress at F represents the ultimate strength or failure stress. G represent the point at which the tissue loses its continuity and load bearing capacity. The modulus is determined as the slope of σ- ε curve in the elastic region within the physiological strain range. The area under the curve between point A–F represents the energy to failure, which can be interpreted as the toughness of the tissue. Note that this curve will differ