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

Figure 3

Passive stretches were sequentially applied with deformations of 0, 10, 20, 30, and 40% to the normal and injured muscles. After steady state was achieved in each deformation, the longitudinal HFU images were scanned and displayed in echogenicity (1st and 2nd rows) and Nakagami parameters (3rd and 4th rows) (a). The injured muscle showed decreased loading forces in 30 and 40% of passive stretch, as compared to the normal muscle in the same strain (), but it still showed increased force, compared to the original length of the injured muscle (#) (b). Increased echogenicity was observed in both normal and injured muscle deformations (c). The quantified Nakagami parameters also increased in passive stretched normal muscles (d). When comparing the longitudinal images between normal and injured muscles, the injured muscle only showed decreased echogenicity ((c), ) and Nakagami parameters ((d), ) at 40% deformation. #: significant difference () from the original length in the same muscle. : significant difference () from the normal muscle in the same strain.

(a)

(b)

(c)

(d)