Appendix 1.
Nomenclature
| Instrumented Measure | Unit | Definition |
|---|---|---|
| Gait - Pace | Pace during straight ahead walking | |
| Gait Cycle Time | s | Duration of a complete gait cycle |
| Cadence | steps/min | Stepping rate |
| Stride Velocity | %h/s | Average gait speed normalized for height |
| Stride Length | %h | Distance between two consecutive heel strikes normalized for height |
| RoM Leg | deg | Range of motion of the leg (calculated from the integrated sagittal angular velocity, approximation of step length). Average of the left and right sides. |
| Gait - Arm & Trunk Movement | Arm and trunk movement during straight ahead walking | |
| Arm Peak Velocity | deg/s | Peak (95%) angular velocity of most affected arm. |
| Arm Swing RoM | deg | Range of motion of most affected arm during arm-swing. |
| Asymmetry Arm Swing RoM | % | Average asymmetry of the left and right arm swing range of motion |
| RoM Trunk Frontal Plane | deg | Average range of motion of trunk in frontal plane |
| RoM Trunk Sagittal Plane | deg | Average range of motion of trunk in sagittal plane |
| RoM Trunk Horizontal Plane | deg | Average range of motion of trunk in horizontal plane |
| Gait - Dynamic Stability | Dynamic stability during straight ahead walking | |
| Double Support Time | % of gait cycle | Percentage of a gait cycle that both feet are on the ground |
| Stance Time | % of gait cycle | Average percentage of a gait cycle that either foot is on the ground |
| Swing Time | % of gait cycle | Average percentage of a gait cycle that either foot is off the ground |
| Turning | 180 degree turn | |
| Peak Velocity | deg/s | Peak (95%) angular velocity of trunk during turning |
| Duration | s | Duration of a 180 degree turn |
| Mean Step Time | s | Average duration of step during 180 degree turn |
| Number of Steps | n | Total number of steps during 180 degree turn |
| Initiation of Gait | Anticipatory postural adjustments (APA) made when attempting to voluntarily initiate the first step to begin walking | |
| APA Duration | s | Time from APA onset to end |
| APA Latency | s | Time from APA onset to first heel strike (from APA onset to peak angular velocity of the stepping leg, approximation of the first step velocity) |
| APA Peak AP | g | Peak trunk acceleration forward from baseline |
| APA Peak ML | g | Peak acceleration toward the stance foot of the lateral trunk acceleration |
| RoM First Step | deg | Range of motion of the leg (calculated from the integrated sagittal angular velocity, approximation of first step length) |
| Duration of First Step | s | Time from toe-off to first heel strike |
| Postural Sway | Standing quietly for 30 seconds. | |
| Sway RMS AP | m/s2 | Root mean square of acceleration time series in anteroposterior direction |
| Sway RMS ML | m/s2 | Root mean square of acceleration time series in mediolateral direction |
| Mean velocity AP | m/s | Mean velocity of center of pressure in anteroposterior direction |
| Mean velocity ML | m/s | Mean velocity of center of pressure in mediolateral direction |
| Centroidal Frequency AP | Hz | Centroidal frequency in anteroposterior direction; variability of the acceleration traces power ranging from 0 to 1 |
| Centroidal Frequency ML | Hz | Centroidal frequency in mediolateral direction; variability of the acceleration traces power ranging from 0 to 1 |
| Frequency Dispersion AP | - | Anteroposterior frequency dispersion; dimensionless measure of variability of the frequency content of the power spectral density (0 for a pure sinusoid, it increases with spectral bandwidth to 1) |
| Frequency Dispersion ML | - | Mediolateral frequency dispersion; dimensionless measure of variability of the frequency content of the power spectral density (0 for a pure sinusoid, it increases with spectral bandwidth to 1) |
| Normalized Jerk AP | - | Smoothness of sway, time derivative of anteroposterior acceleration normalized to range of anteroposterior acceleration excursion and duration |
| Normalized Jerk ML | - | Smoothness of sway, time derivative of mediolateral acceleration normalized to range of mediolateral acceleration excursion and duration |
deg = degree; g = acceleration of gravity; %h = percent of subject’s height; Hz = Herz; n = number; m/s2 = acceleration; s = seconds; - = dimensionless