The first thought-controlled bionic leg

(Nanowerk News) Rehabilitation Institute of Chicago (RIC) research participant Zac Vawter made history on Sunday, November 4, 2012, by climbing 103 floors of Chicago’s Willis Tower using the first “thought-controlled bionic leg”, a neural-controlled prosthetic leg driven by his own thoughts. Vawter, 31, of the Seattle area, was joined by nearly 3,000 others in the world’s tallest indoor stair climb event, SkyRise Chicago, which benefits further RIC research.
RIC’s Center for Bionic Medicine pioneered the Targeted Muscle Reinnervation (TMR) technique which allows amputees to have more natural control of prosthetic devices. Vawter lost his leg in a motorcycle accident three years ago. He received the TMR procedure when his leg was amputated and became part of RIC’s unique research trial about a year ago. He travels to Chicago to work every few months to test this one-of-a-kind prosthetic leg that has a powered knee and ankle. What makes it “bionic” is that it interacts with him. When Vawter pushes on the device to stand-up, the device reads his intent and pushes back on him propelling him up.
Zac Vawter during his 103-story climb of Chicago's Willis Tower
Zac Vawter during his 103-story climb of Chicago's Willis Tower.
“One of the biggest difference for me is being able to take stairs step-over-step like everyone else,” said Vawter. “With my standard prosthesis, I have to take every step with my good foot first and sort of lift or drag the prosthetic leg up. With the bionic leg, it’s simple, I take stairs like I used to, and can even take two at a time.”
SkyRise Chicago is a climb and fundraising event that raises funds for RIC’s world-class clinical care and innovative research. Nearly 3,000 participants climbed 103 flights of stairs of Willis Tower, or hand- cycled the equivalent with specially calibrated hand-cycles, or “virtually” participated through fundraising alone.
“There are approximately 600,000 individuals with lower limb amputation in the United States, and we are hopeful that this neural-controlled technology will allow for more ability and more long-term independence,“ said Levi Hargrove, Ph.D., director of the neural engineering for Prosthetics & Orthotics Lab within RIC’s Center for Bionic Medicine. “Our integrated team of clinicians, prosthetists and engineers are very excited to have climbed with Zac Sunday.”
This work is a result of a grant from The Department of Defense Army’s Telemedicine and Advanced Technology Research Center (TATRC) aimed to improve the control of advanced robotic leg prostheses by adding neural information to the control system. This work is a collaborative effort lead by RIC’s Center for Bionic Medicine, also including the University of New Brunswick, Vanderbilt University, MIT, and URI. The robotic leg prototype Vawter will use during Skyrise was designed by Michael Goldfarb at Vanderbilt University and has undergone extensive testing at both Vanderbilt University and the Rehabilitation Institute of Chicago.
About RIC’s Center for Bionic Medicine
RIC’s Center for Bionic Medicine first launched the “Bionic Arm” in 2005 which allowed a man to control a robotic arm prosthesis by his own neural signals. The procedure, pioneered at RIC, uses Targeted Muscle Reinnervation (TMR) to replant nerves that once went to an amputees amputated limb to new healthy muscle and tissue, allowing the neural information to be used to control a computerized prosthesis more naturally—the user simply thinks about what they want the arm to do. RIC’s "Bionic Arm" technology has been very successful in more than 50 patients worldwide, including several U.S. service members who lost limbs in combat.
Source: Rehabilitation Institute of Chicago