Scientists have helped three amputees merge with their bionic prosthetic legs as they climb over various obstacles without having to look.
The amputees report using and feeling their bionic leg as part of their own body, thanks to sensory feedback from the prosthetic leg that is delivered to nerves in the leg’s stump. Djurica Resanovic lost his leg in a motorbike accident several years ago which resulted in amputation above the knee. Thanks to novel neuroprosthetic leg technology, Resanovic was successfully merged with his bionic leg during clinical trials in Belgrade, Serbia.
After all of these years, I could feel my leg and my foot again, as if it were my own leg,” reports Resanovic about the bionic leg prototype. “It was very interesting. You don’t need to concentrate to walk, you can just look forward and step. You don’t need to look at where your leg is to avoid falling.”
Walking with instinct again
Scientists from a European consortium led by Swiss Institutions, ETH Zurich and EPFL spin-off SensArs Neuroprosthetics, with clinical trials in collaboration with institutions in Belgrade, Serbia, successfully characterized and implemented bionic leg technology with three amputees. The results appear Science Translational Medicine.
“We showed that less mental effort is needed to control the bionic leg because the amputee feels as though their prosthetic limb belongs to their own body,”
explains Stanisa Raspopovic, ETH Zurich professor and co-founder of EPFL spin-off SensArs Neuroprosthetics, who led the study.
“This is the first prosthesis in the world for above-knee leg amputees equipped with sensory feedback. We show that the feedback is crucial for relieving the mental burden of wearing a prosthetic limb which, in turn, leads to improved performance and ease of use.”
Wearing a blindfold and earplugs, Resanovic could feel his/her bionic leg prototype thanks to sensory information that was delivered wirelessly via electrodes surgically placed into the stumps’ intact nervous system.
These electrodes pierce through the intact tibial nerve instead of wrapping around it. This approach has already proven to be efficient for studies of the bionic hand led by Silvestro Micera, co-author of the publication, EPFL’s Bertarelli Foundation Chair in Translational Neuroengineering, professor of Bioelectronics at Scuola Superiore Sant’Anna, and co-founder of SensArs Neuroprosthetics.