A Comparison of Postural Stability during Upright Standing between Normal and Flatfooted Individuals, Based on COP-Based Measures
<p>The participant steps in chalk then takes a step on a sheet of paper. The arch index ratio (R) of the footprint is then calculated [<a href="#B2-entropy-19-00076" class="html-bibr">2</a>].</p> "> Figure 2
<p>Center of pressure (COP) displacement trajectories of a participant standing on a force plate were retrieved for the anterior–posterior (AP) and medial–lateral (ML) directions. The time series signal was then detrended into intrinsic mode functions (IMFs) using the empirical mode decomposition (EMD) method.</p> "> Figure 3
<p>The overall architecture of assessment procedure for postural stability from the COP displacement trajectory of a participant standing on a force plate in normal foot and flatfooted persons. EC: eyes closed; EO: eyes open; MSE: multiscale entropy; MMSE: multivariate multiscale entropy.</p> ">
Abstract
:1. Introduction
2. Materials and Methods
2.1. Participants
2.2. Equipment
2.3. COP-Based Measures
2.3.1. Traditional COP Methods
2.3.2. Entropy Methods
2.4. Data Analysis
2.5. Statistics
3. Results
3.1. Traditional COP-Based Measures
3.2. Entropy Measures
4. Discussion
5. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Participants | Footprint Type (mean ± SD) | p-Value | |
---|---|---|---|
Flatfooted (n = 17) | Normal (n = 37) | ||
Males | 13 | 16 | |
Females | 4 | 21 | |
Arch index (R) | 1.26 ± 0.17 | 0.71 ± 0.09 | 0.000 |
Age (years) | 22.53 ± 1.42 | 23.62 ± 2.29 | 0.076 |
Height (cm) | 169.79 ± 7.93 | 165.76 ± 7.63 | 0.081 |
Weight (kg) | 68.44 ± 13.23 | 60.93 ± 10.35 | 0.051 |
BMI (kg/m2) | 23.59 ± 3.06 | 22.06 ± 2.56 | 0.062 |
Measures (Units) | EO | EC | ||||||
---|---|---|---|---|---|---|---|---|
Flatfooted (n = 17) | Normal (n = 37) | t-Value | p-Value | Flatfooted (n = 17) | Normal (n = 37) | t-Value | p-Value | |
MDIST (mm) | 3.51 ± 1.23 | 2.77 ± 1.10 | 2.23 | 0.030 * | 3.83 ± 2.27 | 3.05 ± 1.19 | 1.66 | 0.102 |
MDIST_AP (mm) | 2.68 ± 1.01 | 2.18 ± 0.89 | 1.81 | 0.077 | 3.01 ± 1.77 | 2.41 ± 0.92 | 1.65 | 0.106 |
MDIST_ML (mm) | 1.73 ± 0.77 | 1.26 ± 0.63 | 2.38 | 0.021 * | 1.77 ± 1.22 | 1.39 ± 0.85 | 1.32 | 0.192 |
RDIST (mm) | 4.03 ± 1.40 | 3.20 ± 1.26 | 2.17 | 0.034 * | 4.44 ± 2.57 | 3.54 ± 1.37 | 1.67 | 0.100 |
RDIST_AP (mm) | 3.32 ± 1.23 | 2.73 ± 1.11 | 1.74 | 0.087 | 3.78 ± 2.19 | 3.02 ± 1.11 | 1.70 | 0.094 |
RDIST_ML (mm) | 2.17 ± 0.95 | 1.57 ± 0.77 | 2.47 | 0.017 * | 2.22 ± 1.51 | 1.73 ± 1.04 | 1.39 | 0.171 |
TOTEX (mm) | 523.8 ± 106.6 | 508.8 ± 81.9 | 0.57 | 0.572 | 602.2 ± 161.6 | 579.7 ± 103.2 | 0.62 | 0.540 |
TOTEX_AP (mm) | 376.6 ± 83.4 | 358.7 ± 52.3 | 0.96 | 0.339 | 442.5 ± 124.9 | 424.3 ± 76.6 | 0.66 | 0.512 |
TOTEX_ML (mm) | 282.6 ± 63.4 | 283.0 ± 57.2 | −0.02 | 0.985 | 312.2 ± 96.8 | 304.0 ± 69.9 | 0.36 | 0.723 |
MVELO (mm/s) | 8.73 ± 1.78 | 8.48 ± 1.37 | 0.57 | 0.572 | 10.04 ± 2.69 | 9.66 ± 1.72 | 0.62 | 0.540 |
MVELO_AP (mm/s) | 6.28 ± 1.39 | 5.98 ± 0.87 | 0.96 | 0.339 | 7.37 ± 2.08 | 7.07 ± 1.28 | 0.66 | 0.512 |
MVELO_ML (mm/s) | 4.71 ± 1.06 | 4.72 ± 0.95 | −0.02 | 0.985 | 5.20 ± 1.61 | 5.07 ± 1.16 | 0.36 | 0.723 |
AREA_CC (mm2) | 160.8 ± 126.9 | 106.3 ± 89.6 | 1.82 | 0.075 | 231.6 ± 370.1 | 130.4 ± 126.3 | 1.50 | 0.141 |
AREA_SW (mm2/s) | 9.84 ± 5.03 | 5.03 ± 7.45 | 1.78 | 0.081 | 12.62 ± 11.85 | 9.06 ± 5.46 | 1.52 | 0.135 |
Measures | EO | EC | ||||||
---|---|---|---|---|---|---|---|---|
Flatfooted (n = 17) | Normal (n = 37) | t-Value | p-Value | Flatfooted (n = 17) | Normal (n = 37) | t-Value | p-Value | |
CI_AP_IMF1 | 26.15 ± 4.51 | 27.64 ± 2.15 | −1.65 | 0.105 | 24.78 ± 4.93 | 26.71 ± 3.3 | −1.69 | 0.098 |
CI_AP_IMF2 | 15.75 ± 4.84 | 17.56 ± 4.07 | −1.43 | 0.16 | 15.69 ± 6.45 | 15.59 ± 5.65 | 0.06 | 0.954 |
CI_AP_IMF3 | 10.17 ± 3.34 | 11.03 ± 3.04 | −0.93 | 0.357 | 10.36 ± 3.08 | 10.17 ± 2.87 | 0.22 | 0.829 |
CI_AP_IMF4 | 11.21 ± 1.30 | 11.44 ± 1.83 | −0.45 | 0.655 | 11.26 ± 1.71 | 10.81 ± 1.71 | 0.91 | 0.368 |
CI_AP_IMF5 | 8.92 ± 0.53 | 9.00 ± 0.780 | −0.37 | 0.711 | 8.54 ± 0.89 | 8.70 ± 0.90 | −0.61 | 0.544 |
CI_AP_IMF6 | 6.47 ± 0.69 | 6.74 ± 0.826 | −1.18 | 0.245 | 6.22 ± 0.67 | 6.67 ± 0.73 | −2.15 | 0.036 * |
CI_AP_IMF7 | 3.46 ± 0.85 | 3.63 ± 1.02 | −0.60 | 0.549 | 3.13 ± 0.82 | 3.59 ± 0.68 | −2.16 | 0.036 * |
Measures | EO | EC | ||||||
---|---|---|---|---|---|---|---|---|
Flatfooted (n = 17) | Normal (n = 37) | t-Value | p-Value | Flatfooted (n = 17) | Normal (n = 37) | t-Value | p-Value | |
CI_ML_IMF1 | 28.30 ± 1.35 | 28.44 ± 1.16 | −0.39 | 0.695 | 28.20 ± 1.16 | 28.516 ± 0.66 | −1.29 | 0.201 |
CI_ML_IMF2 | 21.00 ± 4.15 | 22.24 ± 4.03 | −0.98 | 0.332 | 18.34 ± 6.4 | 21.33 ± 5.36 | −1.78 | 0.081 |
CI_ML_IMF3 | 10.54 ± 4.76 | 11.26 ± 4.65 | −0.53 | 0.599 | 9.44 ± 4.41 | 10.24 ± 3.92 | −0.67 | 0.507 |
CI_ML_IMF4 | 9.37 ± 2.09 | 9.04 ± 2.59 | 0.46 | 0.65 | 9.39 ± 2.19 | 8.79 ± 2.11 | 0.95 | 0.346 |
CI_ML_IMF5 | 8.71 ± 1.19 | 8.85 ± 1.36 | −0.38 | 0.705 | 8.66 ± 1.32 | 8.80 ± 1.32 | −0.36 | 0.719 |
CI_ML_IMF6 | 7.05 ± 0.78 | 7.38 ± 0.86 | −1.33 | 0.188 | 6.75 ± 1.17 | 7.21 ± 0.80 | −1.70 | 0.095 |
CI_ML_IMF7 | 3.72 ± 0.98 | 4.16 ± 0.97 | −1.54 | 0.129 | 3.82 ± 0.82 | 4.07 ± 0.85 | −1.02 | 0.312 |
Measures | EO | EC | ||||||
---|---|---|---|---|---|---|---|---|
Flatfooted (n = 17) | Normal (n = 37) | t-Value | p-Value | Flatfooted (n = 17) | Normal (n = 37) | t-Value | p-Value | |
CI_IMF1 | 5.80 ± 0.45 | 5.78 ± 0.41 | 0.13 | 0.894 | 5.74 ± 0.50 | 5.78 ± 0.52 | −0.27 | 0.787 |
CI_IMF2 | 7.94 ± 1.68 | 7.81 ± 1.07 | 0.33 | 0.74 | 7.48 ± 1.94 | 7.53 ± 1.37 | −0.12 | 0.905 |
CI_IMF3 | 7.30 ± 2.71 | 7.57 ± 2.19 | −0.40 | 0.693 | 7.08 ± 2.40 | 7.16 ± 1.84 | −0.13 | 0.895 |
CI_IMF4 | 9.86 ± 2.22 | 9.63 ± 2.51 | 0.33 | 0.741 | 10.37 ± 2.28 | 9.41 ± 1.96 | 1.58 | 0.119 |
CI_IMF5 | 12.53 ± 1.45 | 12.02 ± 1.78 | 1.04 | 0.303 | 12.49 ± 1.71 | 12.22 ± 1.85 | 0.50 | 0.619 |
CI_IMF6 | 12.24 ± 1.11 | 12.41 ± 1.26 | −0.48 | 0.633 | 11.88 ± 1.34 | 12.27 ± 1.47 | −0.93 | 0.357 |
CI_IMF7 | 10.64 ± 1.94 | 10.82 ± 1.23 | −0.42 | 0.679 | 10.36 ± 1.43 | 10.74 ± 1.16 | −1.06 | 0.296 |
Measures | EO | EC | ||||||
---|---|---|---|---|---|---|---|---|
Flatfooted (n = 17) | Normal (n = 37) | t-Value | p-Value | Flatfooted (n = 17) | Normal (n = 37) | t-Value | p-Value | |
CI_AP_IMF5,6 | 8.41 ± 0.72 | 8.65 ± 0.75 | −1.12 | 0.266 | 8.06 ± 0.92 | 8.35 ± 0.83 | −1.17 | 0.249 |
CI_ML_IMF5,6 | 8.93 ± 1.00 | 9.39 ± 1.19 | −1.37 | 0.176 | 8.67 ± 1.31 | 9.37 ± 0.86 | −2.35 | 0.023 * |
CI_IMF5,6 | 13.13 ± 1.36 | 13.52 ± 1.05 | −1.14 | 0.258 | 12.85 ± 1.23 | 13.41 ± 1.30 | −1.48 | 0.144 |
CI_AP_IMF6,7 | 5.06 ± 0.92 | 5.53 ± 0.67 | −2.09 | 0.042 * | 4.50 ± 0.94 | 5.51 ± 0.73 | −4.30 | 0.000 * |
CI_ML_IMF6,7 | 5.71 ± 0.82 | 6.22 ± 0.83 | −2.12 | 0.039 * | 5.76 ± 1.12 | 6.18 ± 0.83 | −1.53 | 0.133 |
CI_IMF6,7 | 11.36 ± 1.43 | 11.57 ± 1.20 | −0.58 | 0.564 | 11.04 ± 1.05 | 11.54 ± 1.09 | −1.59 | 0.118 |
CI_AP_IMF5,67 | 7.29 ± 1.04 | 7.69 ± 1.10 | −1.24 | 0.222 | 7.26 ± 0.82 | 7.71 ± 0.68 | −2.12 | 0.039 * |
CI_ML_IMF5,67 | 8.09 ± 1.13 | 8.82 ± 1.31 | −1.97 | 0.054 | 8.15 ± 1.49 | 8.92±0.96 | −2.31 | 0.025 * |
CI_IMF5,6,7 | 12.57 ± 1.04 | 12.82 ± 1.40 | −0.66 | 0.512 | 12.57 ± 0.97 | 13.19 ± 1.13 | −1.94 | 0.058 |
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Chao, T.-C.; Jiang, B.C. A Comparison of Postural Stability during Upright Standing between Normal and Flatfooted Individuals, Based on COP-Based Measures. Entropy 2017, 19, 76. https://doi.org/10.3390/e19020076
Chao T-C, Jiang BC. A Comparison of Postural Stability during Upright Standing between Normal and Flatfooted Individuals, Based on COP-Based Measures. Entropy. 2017; 19(2):76. https://doi.org/10.3390/e19020076
Chicago/Turabian StyleChao, Tsui-Chiao, and Bernard C. Jiang. 2017. "A Comparison of Postural Stability during Upright Standing between Normal and Flatfooted Individuals, Based on COP-Based Measures" Entropy 19, no. 2: 76. https://doi.org/10.3390/e19020076