A comparison of energy expenditure by a high level trans-femoral amputee using the Intelligent Prosthesis and conventionally damped prosthetic limbs

Abstract

Comparisons were made between the Intelligent Prosthesis (IP), Mauch and pneumatic swing phase control damping systems on the same prosthesis worn by a high level trans-femoral amputee. Speeds self selected by corridor walking (4.4 – 5.5 kmh⁻¹) proved not to be sustainable for treadmill walking. Comfortable speeds were attained when the subject walked on a treadmill at 2.0, 2.6 and 3.2 kmh⁻¹ in two tests for each prosthesis type. Oxygen uptake (V˙O₂), cadence and heart rate were measured over 5 minute walks interspersed with rest periods. Spearman's correlation was used to test for differences between prosthesis types at each speed. At the two slower speeds no significant difference was found, but at the higher speed of 3.2 kmh⁻¹, the IP was associated with a significantly lower V˙O2 (pVO₂ for different limb types (p=0.015). A square law function was fitted to the mean V˙O₂ for each prosthesis type by the method of least squares regression. ANOVA demonstrated a significant difference between velocity coefficients for the different prosthesis types (p3.2km h⁻¹) the IP gave a lower oxygen uptake by about 10%.