Table 1 Predictor variables separated by category of participant information. Note that 2 separate groups of models were used: Demographic, anthropometric, and knee OA descriptor variables were used in all models, while the gait, posture, and movement characteristics were separated by whether they were derived using clinically accessible or laboratory-derived approaches. Note that the laboratory-derived data were from the FLAT condition trials
Demographics, anthropometrics, and descriptors of knee osteoarthritis | ||
 Age (years) | ||
 Sex (male/female) | ||
 Body mass index (kg/m2) | ||
 Foot posture index (-12 to + 12) | ||
 Numerical rating scale of knee pain (0 to 10) | ||
 Foot function index pain score (normalized 25% to 100%) | ||
 Kellgren & Lawrence grade (dichotomized as KL2 or KL3–4) | ||
Gait, posture, and movement characteristics | ||
| Â | Clinically-Accessible | Laboratory-Derived |
Gait speed (dm/s) | Fixed distance between two photoelectric timing gates, divided by time elapsed to cross from one gate to the other | The distance between heel strike to heel strike, divided by time elapsed between the heel strike events |
Ankle/subtalar eversion motion ( ° ) | Range between resting posture and end range eversion | Frontal plane ankle/subtalar joint angle excursion between initial contact and peak eversion |
Foot progression angle ( ° ) | Foot position measured during walking over a length of paper with wet socks | Mean foot progression angle during midstance (15 to 50% normalized stance) |
Frontal plane knee alignment ( ° ) | Tibial inclination in frontal plane, measured by digital smartphone inclinometer | Mean frontal plane knee angle during midstance (25 to 50% normalized stance) |