Table 1.
Vibration perception thresholds and mechanical skin properties in healthy subjects and individuals with diabetes.
| Variable | CG | DM | DPN | Statistics | d.f. | p-Value | |
|---|---|---|---|---|---|---|---|
| Heel | VPT 30 Hz (µm) | 15.4 [7.3–31.3] # |
23.0 [14.4–57.9] § |
104.4 [46.5–196.9] #§ |
18.72 | 2 | <0.01 |
| VPT 200 Hz (µm) | 2.0 [0.6–5.9] # |
1.1 [0.7–4.4] § |
18.0 [5.1–31.0] #§ |
9.52 | 2 | <0.01 | |
| thickness (mm) | 0.78 ± 0.17 | 0.94 ± 0.41 | 0.86 ± 0.40 | 5.18 | 2 | 0.08 | |
| hardness (Shore 00) |
28.6 ± 7.9 * | 33.4 ± 8.3 | 39.0 ± 8.8 * | 7.89 | 2 | <0.01 | |
| MET I | VPT 30 Hz (µm) | 10.7 [4.9–19.9] # |
9.9 [6.9–24.1] § |
73.9 [33.6–191.8] #§ |
21.29 | 2 | 6 × 10−8 |
| VPT 200 Hz (µm) | 1.9 [0.4–8.6] # |
1.1 [0.5–4.7] § |
23.7 [16.5–51.1] #§ |
12.82 | 2 | <0.01 | |
| thickness (mm) | 0.72 ± 0.10 | 0.78 ± 0.41 | 0.71 ± 0.40 | 1.56 | 2 | 0.46 | |
| hardness (Shore 00) |
29.1 ± 14.0 | 27.1 ± 7.5 | 31.3 ± 8.4 | 0.56 | 2 | 0.57 |
Notes: p-values, statistics and degrees of freedom (d.f.) are from Kruskal–Wallis rank sum tests for skin thickness and ANOVAs performed for skin hardness and VPTs. Pairwise comparisons using t-tests with pooled SD were done for all VPTs (#, § all p-values < 0.01) and for skin hardness at the heel (* p < 0.01). p-values were adjusted by using the Bonferroni method. VPT values are reported as median and interquartile range. Mechanical skin properties are reported as mean ± SD.