Fig. 4.

The upper ordinate shows the ‘external’ muscular work per unit distance, W_ext (J/kg/m). The lower ordinate gives the recovery of W_ext along the stride, R, due to the pendulum-like mechanism of gait, as a function of waking velocity (m/s), given on the abscissa. The crossed symbols give mean and 95% confidence limits on both axes of normative values recorded from 125 steps made by eight healthy controls. The filled dots refer to four AK (labeled a) and to three BK (labeled b) amputees. Normative and amputees’ data are reproduced from a previous study (Tesio et al., 1998a, 1998b) with the authors’ and publishers’ permission. The triangle, the square and the open circle refer to KRP patients A, B and C, respectively (see Table 1 for details). The W_ext and R values of patients A, B, and C are as follows: 0.25 and 0.70; 0.24 and 0.86; and 0.22 and.74, respectively.