Table 1.
Biomechanical descriptors and their trends with stiffness
| pL | pQ | vlb | vub | |
|---|---|---|---|---|
| Hip | ||||
|
Cross-leg diff. in max. hip height Cross-leg difference in stepwise maximum hip height |
0.666 | 0.289 | − | − |
|
Cross-leg RMS diff. hip angle Cross-leg root mean squared difference of stepwise hip angle trajectories |
0.421 | 0.759 | − | − |
|
Cross-leg RMS diff. hip moment Cross-leg root mean squared difference of stepwise hip moment trajectories |
0.066 | 0.950 | − | − |
|
Pelvic tilt variance Pelvic tilt variance |
2e-4* | 0.039 | - 2.0 | 69.1 |
| Knee | ||||
|
Affected knee ROM Affected-side knee range of motion |
2e-4* | 0.177 | − | − |
|
Affected knee peak flex. moment Affected-side peak knee flexion moment |
6e-13* | 0.381 | − | − |
|
Affected knee peak ext. moment Affected-side peak knee extension moment |
0.002 | 0.508 | − | − |
|
Unaffected knee ROM Unaffected-side knee range of motion |
0.653 | 0.930 | − | − |
|
Unaffected knee peak early flex. angle Unaffected-side peak knee flexion angle in the first half of stance phase |
2e-16* | 0.426 | − | − |
|
Unaffected knee peak early ext. moment Unaffected-side peak knee extension moment in the first half of stance phase |
2e-8* | 8e-3 | 8.2 | 72.0 |
|
Cross-leg RMS diff. knee angle Cross-leg root mean squared difference of stepwise knee angle trajectories |
0.451 | 0.092 | − | − |
|
Cross-leg RMS diff. knee moment Cross-leg root mean squared difference of stepwise knee moment trajectories |
0.546 | 0.110 | − | − |
|
Cross-leg diff. in peak knee ext. moment Cross-leg difference of stepwise peak knee extension moments |
0.036 | 0.584 | − | − |
| Ankle | ||||
|
Affected ankle peak DF angle Affected-side peak (prosthetic) ankle dorsiflexion angle |
3e-33* | 0.020 | 22.4 | 255 |
|
Affected ankle ROM Affected (prosthetic) ankle range of motion |
3e-37* | 5e-3 | 40.2 | 215 |
|
Affected ankle peak PF moment Affected-side peak (prosthetic) ankle plantar flexion moment |
1e-10* | 0.019 | 7.2 | 100 |
|
Affected ankle peak power Affected-side peak (prosthetic) ankle power |
7e-18* | 0.334 | − | − |
|
Unaffected ankle ROM Unaffected-side ankle range of motion |
0.576 | 0.863 | − | − |
|
Unaffected ankle peak PF moment Unaffected-side peak ankle plantar flexion moment |
0.131 | 0.598 | − | − |
|
Cross-leg RMS diff. ankle angle Cross-leg root mean squared difference of stepwise ankle angle trajectories |
0.182 | 9e-4* | - 18.0 | 3.95 |
|
Cross-leg RMS diff. ankle moment Cross-leg root mean squared difference of stepwise ankle moment trajectories |
4e-4* | 0.535 | − | − |
|
Cross-leg diff. in peak ankle PF moment Cross-leg difference of stepwise peak ankle plantar flexion moments |
1e-5* | 0.167 | − | − |
|
Cross-leg diff. in peak ankle power Cross-leg difference of stepwise peak ankle powers |
0.099 | 0.991 | − | − |
| Other | ||||
|
Affected step prop. of total stride duration Affected-side step duration as a proportion of total stride duration |
0.017 | 0.451 | − | − |
|
Affected step prop. of total stride distance Affected-side step distance as a proportion of total stride distance |
0.276 | 0.965 | − | − |
Twenty-five descriptors were evaluated for first- and second-order fit with preference-normalized VSPA stiffness. The table shows p-values for the linear (pL) and quadratic (pQ) terms of the LMEM fit to each descriptor. For descriptors with pQ < 0.05, the lower (vlb) and upper (vub) bounds on the 95% CI for the vertex stiffness (percent deviation from preferred) are also shown.
*Indicates significance at the α = 0.05 level (Bonferroni correction for 25 tested hypotheses)