Powerful Possibilities for Prosthetic Legs

Image credit: Shirley Ryan AbilityLab

In a world-first, a team of researchers led by Chicago’s Shirley Ryan AbilityLab is working to develop a powered bionic leg prosthesis using a novel combination of osseointegration, targeted muscle reinnervation (TMR) and pattern-recognition control.

The project is set to mark an exciting innovation within the field of bionic limbs, with millions of people living with limb loss globally.

With $US1.5 million in funding from the US Department of Defense, the study sees the Shirley Ryan AbilityLab join together with Swedish osseointegration pioneers, Integrum as well as Northwestern Medicine to perform the implant and TMR surgery on eight patients. Clinical trials will then evaluate patients’ function and comfort with the technology.

In a recent interview with Amplitude Magazine, researcher Dr Levi Hargrove said the innovation could be “trailblazing”, resulting in a more comfortable, lighter and adaptable powered prosthetic leg than offered by current options.

“Powered legs are generally a little bit heavier than non-powered devices, so we’re interested in using osseointegration for better suspension… then the other component of the study is to try to figure out how we can send muscle signals back into the controller for these legs,” Dr Hargrove told Amplitude.

“We’ve been using neural signal decoding, or EMG [electromyography] decoding, and it’s been a real challenge to record lower-limb EMG signals inside of a socket. We’ve been doing this for decades with arms, but in legs, putting EMG sensors inside the socket and making them comfortable is very challenging.

“Individuals who have had osseointegration don’t need a socket, so this allows us to experiment with different ways to collect EMG signals in a more comfortable way and, hopefully, get a cleaner signal. And we hope this will allow us to make even better control algorithms for these legs.”

Read the full interview via Amplitude Magazine, or head to the Shirley Ryan AbilityLab website for further details.