Table 1.
Variables, side, and mean angles for the 2-dimensional markerless (2D ML) method and 3-dimensional gait analysis (3D GA)
| Gait variables (°) | 2D ML | 3D GA | Difference | Correlation | ||||
| and side | mean (SD) | mean (SD) | mean (95% CI) | p-valuea | 95% LoA | coefficient | p-valueb | |
| Knee flexion at initial contact | ||||||||
| Right | 26.1 (9.5) | 19.1 (9.8) | 7.0 (5.0–9.0) | < 0.001 | –0.9 to 14.8 | 0.16 | 0.5 | |
| Left | 26.8 (10.6) | 20.6 (8.5) | 6.3 (4.2–8.2) | < 0.001 | –1.6 to 14.1 | 0.47 | 0.05 | |
| Knee flexion at loading response | ||||||||
| Right | 32.4 (9.5) | 26.3 (8.7) | 6.1 (4.2–8.0) | < 0.001 | –1.1 to 13.4 | 0.22 | 0.4 | |
| Left | 34.0 (9.3) | 27.7 (7.1) | 6.3 (4.2–8.2) | < 0.001 | –1.6 to 14.1 | 0.49 | 0.04 | |
| Knee flexion in stance | ||||||||
| Right | 17.3 (11.7) | 10.6 (12.5) | 6.7 (4.9–8.3) | < 0.001 | –0.2 to 13.5 | –0.19 | 0.4 | |
| Left | 17.5 (9.1) | 12.2 (9.1) | 5.3 (3.1–7.6) | < 0.001 | –3.5 to 14.1 | –0.052 | 0.8 | |
| Knee flexion in swing | ||||||||
| Right | 60.3 (11.4) | 55.4 (9.8) | 5.0 (2.7–7.3) | < 0.001 | –4.1 to 13.9 | 0.26 | 0.3 | |
| Left | 59.6 (8.4) | 56.4 (7.2) | 3.3 (1.3–5.2) | < 0.001 | –4.5 to 11.1 | 0.31 | 0.2 | |
Mean difference calculated by subtracting the 3D GA angle from the 2D ML angle in degrees (SD, standard deviation; CI, confidence interval; LoA, limits of agreement).
a
p-value of the mean difference.
b
p-value of the Spearmen correlation coefficient.