Cross-Sectional Nakagami Images in Passive Stretches Reveal Damage of Injured Muscles

Figure 4

Passive stretch was sequentially applied to both normal and injured muscle as depicted in Figure 3, but HFU images were obtained by scanning the muscle in cross section (a). Normalized stresses during various passive stretches were derived from the loading force and muscle cross-sectional area measured from the HFU images (b). Significant differences were found between normal and injured muscles in each strain, except at 40% deformation. Significant decreases of echogenicity were observed in the cross-sectional images of injured muscles under different strains (c). Instead of showing increased patency of Nakagami parameters during increased strain, the cross-sectional Nakagami parameters were kept at the same level in the injured muscle (d). #: significant difference () from the original length in the same muscle. : significant difference () from the normal muscle in the same strain, bar = 1 mm.

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