TABLE 2:
Gait analysis during overground walking and wading.
| Overground walking | Wading | |||
|---|---|---|---|---|
| Parameter | wt | Pax7-Cre/cKO | wt | Pax7-Cre/cKO |
| IC (height; mm) | 23.6 ± 0.6 | 19.9 ± 1.2** | 25.7 ± 0.9 | 24.7 ± 0.02 |
| Ankle (height; mm) | 14.2 ± 0.3 | 10.9 ± 0.4 | 22.3 ± 0.01 | 17.2 ± 0.2*** |
| Toe (height; mm) | 8.4 ± 0.9 | 5.9 ± 1.5*** | 11.4 ± 0.5 | 8.8 ± 0.02* |
| Base tail (height; mm) | 18.5 ± 0.6 | 14.2 ± 0.9** | 20.8 ± 0.04 | 17.4 ± 0.6 |
| Middle tail (height; mm) | 23.9 ± 1.2 | 7.6 ± 1.3*** | 19.4 ± 0.4 | 10.0 ± 0.7* |
| Tip of the tail (height; mm)a | 23.6 ± 1.8 | 2.6 ± 1.3*** | 11.4 ± 0.1 | 2.5 ± 0.6* |
| External rotation of HLs (deg)b | 25.1 ± 0.9 | 32.7 ± 2.2*** | N.A. | N.A. |
| Distance between HPs (mm/g)c | 1.6 ± 0.2 | 2.3 ± 0.1*** | 1.7 ± 0.1 | 2.6 ± 0.1*** |
| Retraction of HLs (deg)d | N.A. | N.A. | 70.9 ± 1.3 | 56.3 ± 1.9* |
| MTP velocity (cm/s)e | 22.2 ± 1.0 | 16.0 ± 0.3** | 16.3 ± 1.3 | 9.6 ± 0.7*** |
| Velocity (cm/s)f | N.A. | N.A. | 19.0 ± 1.6 | 12.9 ± 0.4** |
Mice placed in a long, horizontal compartment were video recorded while walking on dry ground or wading through shallow water (see Supplemental Figure S6D). Each step while walking/wading over the distance of the platform was analyzed, and values were averaged. Note that under both experimental conditions, the heights of different bony landmarks were lower in Pax7-Cre/cKO than in wt control mice, demonstrating weaker body support. Mice examined: wt, 27; Pax7-Cre/cKO, 20. Mean ± SEM. N.A., not analyzed.
aTail dragging suggested abnormal tail coordination.
bMore extensive external rotation of HLs was measured as the angle between the HL and the anterior–posterior body axis.
cThe larger distance between hindpaws (HPs) suggested loss of HL strength.
dHL retraction (angle between HP-IC and IC-ground axes; see also Supplemental Figure S6D, red lines) during swing phase of HLs appeared more acute in Pax7-Cre/cKO mice, suggesting abnormal iliac crest–HL coordination.
eVelocity of metatarsophalangeal joint (MTP) movement.
fNote that the speed of wading was significantly lower in Pax7-Cre/cKO than in wt mice.
*p < 0.05, **p < 0.01, ***p < 0.001, unpaired Student's t test.