Powered hip exoskeleton improves walking economy in individuals with above-knee amputation

Above-knee amputation severely reduces the mobility and quality of life of millions of individuals. Walking with available leg prostheses is highly inefficient, and poor walking economy is a major problem limiting mobility. Here we show that an autonomous powered hip exoskeleton assisting the residual limb significantly improves metabolic walking economy by 15.6 +/- 2.9% (mean +/- s.e.m.; two-tailed paired t-test, P = 0.002) in six individuals with above-knee amputation walking on a treadmill. The observed metabolic cost improvement is equivalent to removing a 12-kg backpack from a nonamputee individual. All participants were able to walk overground with the exoskeleton, including starting and stopping, without notable changes in gait balance or stability. This study shows that assistance of the user's residual limb with a powered hip exoskeleton is a viable solution for improving amputee walking economy. By significantly reducing the metabolic cost of walking, the proposed hip exoskeleton may have a considerable positive impact on mobility, improving the quality of life of individuals with above-knee amputations. In individuals with above-knee amputation, a powered hip exoskeleton, which reduces the metabolic cost of walking by adding energy at the hip joint, greatly improves walking economy and has the potential to improve mobility.

Automated summary

The study demonstrates that an autonomous powered hip exoskeleton can significantly improve walking economy and therefore quality of life for individuals with above-knee amputation. The exoskeleton, which adds energy at the hip joint, greatly reduces the metabolic cost of walking, similar to removing a 12-kg backpack from a nonamputee. This solution has the potential to enhance mobility and improve the overall well-being of above-knee amputees.