Bionic leg makes walking easier and safer for amputees

The prosthetic leg uses sensors to mimic messages sent by nerves, making it easier to adjust gait and speed depending on the walking surface.

Spotted: Scientists at ETH Zurich research institute have developed an artificial leg that mimics how nerve endings communicate with the knee. The prosthetic’s sensors make it easier and safer for amputees to walk, the scientists say.

Traditional artificial limbs lack the nerve endings needed to adjust gait and muscle pressure. That can lead to injury and make it difficult for an above-the-knee amputee to adapt to different types of surfaces. 

The bionic prosthetic uses sensors and electrodes to send sensory information to the body, mimicking the messages sent by nerves. Signals are sent from the sole of the foot and the prosthetic’s knee joint to electrodes in the wearer’s thigh. The electrodes then send pulses that allow the wearer to “feel” the artificial foot and knee. 

In a three-month trial, the volunteers reported finding it easier to walk on different surfaces. Monitoring also showed that walking was less mentally tasking. The team reports that the bionic prosthetic also addresses health issues like phantom leg pain. 

The ETH Zurich research institute team is working with Swiss startup SensArs and Germany’s University of Freiburg on the bionic prosthetic. The team is now planning on running a larger study on the system.