There are two million people with amputations in the U.S. For many of these patients, prosthetic devices offer greater mobility. Now, researchers are testing a new generation of prosthetics that are like nothing you’ve seen.
Not much slows down Zac Vawter. Not even an amputated leg. “I lost my leg in a motorcycle accident,” Zac said.
Zac received this prosthetic. It helps him get around, but has its limitations. “If I were to sit down and leave the knee locked, it would stay locked,” Zac explained.
But this thought-controlled myoelectric leg does what Zac’s prosthetic can’t. Before Zac could use it, orthopedic surgeon Doug Smith took nerves from his lower leg and redirected them to his hamstring muscle.
“Instead of firing when you think about bending your knee, it would fire when you think about raising your ankle,” Doug Smith, MD, Orthopedic Surgeon, Harborview/UW Medicine, explained.
When Zac wants to move the leg, the brain signal travels down his spinal cord, through the nerves; electrodes in the prosthetic pick up signals from the muscles.
“You can have a prosthetic device that actually works according to your thought,” Dr. Smith said. The device is still being studied, so Zac can’t take it home, but he looks forward to the day he can.
“Stairs with that leg, the ‘bionic leg,’ is really phenomenal,” Zac said. Until now—only thought-controlled arms were available. Although the cost of the “bionic leg” hasn’t been determined, researchers say a version could be available for consumer use within three to five years.