Table 2.
Ultrasonographic measurements of rectus femoris among robust, pre-frail, and frail groups
| Ultrasonographic findings of RF (mean ± SD) (n = 301) | Robust (n = 102) | Pre-frail (n = 125) | Frail (n = 74) | p value |
|---|---|---|---|---|
| Thickness (mm)* | 12.45 ± 2.58a | 11.6 ± 2.48b | 11.12 ± 2.32b | 0.002 |
| CSA (mm2)** | 4.2 (1.7–10.8)a | 3.9 (1.6–7.9)a,b | 3.7 (1.8–7.2)b | 0.009 |
| Muscle stiffness (kPa)** | 15.25 (3.63–33.0) | 15.75 (5.15–30.5) | 14.38 (4.25–35.25) | 0.802 |
| Fascicle length (mm)** | 55.0 (39.0–70.0)a | 53.0 (38.0–66.0)b | 53.7 (36.3–66.7)a,b | 0.043 |
| Pennation angle (degree)* | 11.19 ± 2.12a | 10.12 ± 2.27b | 9.14 ± 1.85c | <0.001 |
| Hyperechogenicity (n/%) | 8 (7.8) | 9 (7.2) | 10 (13.5) | 0.285 |
Bolds are statistically significant values
RF rectus femoris muscle; CSA cross-sectional area
*Mean ± SD
** Median(min–max)
a,b,c The groups with the same letters are not significantly different according to pairwise comparisons