Brain-controlled bionic leg helps amputees to walk and climb stairs

A brain-controlled bionic leg has allowed people with amputations to walk more quickly and navigate stairs and obstacles more easily ina groundbreaking trial.

- Hannah Devlin

The device allows the wearer to flex, point and rotate the foot of the prosthetic using their thoughts. This led to a more natural gait, improved stability on stairs and uneven terrain and a 41% increase in speed compared with a traditional prosthetic. The bionic leg works by reading activity in the patient’s residual leg muscles and using these signals to controlan electrically powered ankle. “Noone has been able to show this level of brain control that produces a natural gait, where the human’s nervous system is controlling the movement, not a robotic control algorithm,” said Prof Hugh Herr, a codirector of the K Lisa Yang centre for bionics at the Massachusetts Institute of Technology (MIT) and the senior author of the study.

"Not only will they be able to walk on a flat surface, but they'll be able to go hiking or dancing because they'll have full control over their movement," he added.

Herr is himself a double amputee, having lost both legs to severe frostbite after being caught in a blizzard during a rock-climbing trip in 1982.