Zurich medtech reveals prosthetic leg users can ‘feel’

A Zurich-led research team has developed a bionic prosthetic leg that allows its user to ‘feel’ their foot and knee in real time, allowing them to walk with less effort.

An international team of researchers led by university ETH Zurich and Lausanne-based start-up company SensArs has developed an interface to connect a leg prosthesis with the residual nerves present in the user’s thigh, thus providing sensory feedback. The bionic prosthesis has tactile sensors on the sole of its foot, that connect to electrodes in the thigh. These stimulate the residual leg nerves via electrical pulses, essentially letting the user ‘feel’ the prosthesis’ foot and knee.

Zurich is home to an innovative life sciences cluster, drawing on the strengths of its universities such as ETH Zurich, and developments such as the Bio-Technopark Schlieren. Besides biotech and pharma, medical technology is particularly strongly represented in Zurich.

Zurich is set to host ICPE 2020, the International Conference on Prosthetic Engineering, in January 2020. It will bring together leading academic scientists and researchers to share their experiences and research results on all aspects of Prosthetic Engineering.

Two amputee test subjects tried the new prosthesis out over a three-month period. Oxygen consumption-monitoring masks indicated that walking was considerably less physically-demanding; measurements of their brain activity suggested that the system made walking less mentally-demanding.

As an added benefit, when the electrodes were activated independently of the prosthesis – stimulating the leg nerves for prescribed periods of time – pre-existing phantom limb pain was significantly reduced in one test subject, and eliminated in the other.

Stanisa Raspopovic, a Professor at the Institute of Robotics and Intelligent Systems at ETH Zurich, says: “This proof-of-concept study shows how beneficial it is to the health of leg amputees to have a prosthesis that works with neural implants to restore sensory feedback.”

The scientists are now planning a longer, larger study, while SensArs is working on a wireless neurostimulation device that can be fully implanted into the patient like a pacemaker, that can be brought to market.


(via ETH Zurich, New Atlas, Meeting Zurich)