Figure 2. Notch tension testing of tendon fascicles.

(a) With increasing grip-to-grip strain, the notch widened and the photobleached lines became steeply angled, representing shear strains developing within the tissue. Consistently at 4% grip-to-grip strain, discontinuities in the photobleached lines first appeared at the location 4 mm from notch (red arrows). These discontinuities propagated parallel to the fascicle axis demarcating the interface between the cut and uncut portions of the tissue. (b) At all non-zero distances from the notch, the axial strains (ε_yy) on the uncut side of the tissue exhibit gradients similar to those seen in the gel (Fig. 1c). Scale bars, 200 μm.