Figure 5

Group results of the experimental data. (a) 3D scatterplot of the relationship between the medio-lateral coordinates of centroids in EMG and US identified area, considering the effect of the depth in US. The surface represents the best fit of the multiple regression model. (b) Scatterplots of the MU divided by the US identification depth. From left to right: depth < 14 mm (N = 60), depth > 14 mm and < 23 mm (N = 59), depth > 23 mm (N = 61).