Effects of a powered ankle-foot prosthesis on kinetic loading of the unaffected leg during level-ground walking

Table 3 Unaffected leg resultant ground reaction force impact peaks and loading rates

Speed	Unaffected leg 1^stpeak GRF (N/kg)				Unaffected leg GRF rate (N/kg/s)
(m/s)	Passive	Powered	% Diff	Control	Passive	Powered	% Diff	Control
0.75	9.97 ± 0.21*^	9.76 ± 0.13	-2.1	9.79 ± 0.27	71.7 ± 36.6	68.8 ± 26.2	-4.0	49.2 ± 16.5
1.00	10.39 ± 0.40*	9.75 ± 0.22	-6.2	9.86 ± 0.37	87.0 ± 39.2	82.5 ± 23.1	-5.2	73.5 ± 15.0
1.25	11.33 ± 0.67*^	10.52 ± 0.75	-7.2	10.62 ± 0.39	118.7 ± 41.9^	103.7 ± 28.8^	-12.6	79.6 ± 7.4
1.50	12.77 ± 1.10*^	11.41 ± 1.28	-10.7	11.58 ± 0.75	137.1 ± 53.2	123.6 ± 22.9	-9.8	104.5 ± 18.9
1.75	13.87 ± 1.24^	13.42 ± 1.70	-3.3	12.32 ± 0.41	176.6 ± 46.8	160.5 ± 44.6	-9.1	151.6 ± 43.5

Average ± S.D. resultant ground reaction force impact peaks and resultant ground reaction force loading rates of each subject with an amputation using a passive-elastic (Passive) or powered (Powered) prosthesis, and non-amputee subjects (Control) across a range of walking speeds. The decreases in peak GRFs and loading rates between the passive-elastic and powered prostheses are shown as a percentage difference (% Diff). * indicates a significant difference (P ≤ 0.05) between subjects with an amputation using the passive-elastic versus powered prostheses. ^ indicates a significant difference (P ≤ 0.05) between subjects with an amputation and non-amputees (Control). P-values for GRF loading rates between subjects with an amputation using the passive-elastic versus powered prostheses were 0.81, 0.70, 0.27, 0.36, and 0.14 at speeds of 0.75, 1.00, 1.25, 1.50, and 1.75 m/s, respectively.

ISSN: 1743-0003