Amputees put bionic prosthetic legs to the test

Biomedical engineering company Össur has successfully tested its thought-controlled bionic prosthetic leg in two volunteer amputees. While Össurs’ ‘smart limbs’ – powered by batteries and controlled and moved by algorithms and sensors – are capable of real-time learning and automatically adjust to their user’s gait, speed and terrain, they still require some conscious, intentional thought from the user.

However, implanted myoelectric sensors (IMES) inserted in a patient’s residual muscle tissue means the prostheses can mimic the natural biological, often subconscious, process of moving lower limbs. This is achieved by the IMES receiving electrical impulses from the user’s brain and relaying this information to a receiver located inside the artificial limb, which enables subconscious, real-time control and faster, more natural responses and movements. 

Dr Thorvaldur Ingvarsson, head of R&D at Össur, said: “One year ago, we implanted sensors into individuals – one transtibial amputee (below-knee) and one transfemoral (above-knee) amputee. They have been living with this for a year with good results. They tell us it’s more easy to walk around, go upstairs, downstairs, and so on.”

Gummi Olafsson is one of the patients trialling the IMES sensor technology in conjunction with a prosthetic “Proprio foot” developed by Össur with a battery-powered motorised ankle. He said that following the implant surgery, he gained control of his foot in 10 minutes.