As It Happens

This man was able to grasp his wife's hand — and feel it — with new prosthetic technology

Keven Walgamott didn't like wearing a prosthetic arm — until he used one to gently grasp his wife's hand. 

Keven Walgamott also plucked a grape and picked up an egg without breaking it

Keven Walgamott grasps his wife's hand using an advanced prosthetic arm that recreates the sensation of touch. (University of Utah Center for Neural Interfaces)
Listen6:34

Read Story Transcript

Keven Walgamott didn't like wearing a prosthetic arm — until he used one to gently grasp his wife's hand.

The West Valley City, Utah, real estate agent lost his left hand in an electrical accident 17 years ago. Since then, he's tried out a few different prosthetic limbs, but always found them too clunky and uncomfortable. 

Then he decided to work with the University of Utah in 2016 to test out new prosthetic technology that mimics the sensation of human touch, allowing Walgamott to perform delicate tasks with precision — including shaking his wife's hand.  

"I extended my left hand, she came and extended hers, and we were able to feel each other with the left hand for the first time in 13 years, and it was just a marvellous and wonderful experience," Walgamott told As It Happens guest host Megan Williams. 

Watch Keven Walgamott shake his wife's hand with a prosthetic limb that mimics touch:

Keven Walgamott shakes his wife's hand thanks to new technology from the University of Utah that recreates the sensation of human touch. 0:15

Walgamott, one of seven participants in the University of Utah study, was able to use an advanced prosthetic hand called the LUKE Arm to pick up an egg without cracking it, pluck a single grape from a bunch, hammer a nail, take a ring on and off his finger, fit a pillowcase over a pillow and more. 

The LUKE arm was developed by DEKA Research & Development Corp., and named after Luke Skywalker's robotic hand in The Empire Strikes Back.

The findings were published Wednesday in the journal Science Robotics. 

What does it feel like?

While performing the tasks, Walgamott was able to actually feel the items he was holding and correctly gauge the amount of pressure he needed to exert — mimicking a process the human brain does automatically.

"I was able to feel something in each of my fingers," he said. "What I feel, I guess the easiest way to explain it, is little electrical shocks."

Those shocks — which he describes as a kind of a tingling sensation — intensify as he tightens his grip. 

"Different variations of the intensity of the electricity as I move my fingers around and as I touch things," he said. 

 

The reason most prosthetic hands so feel clumsy and unnatural is because they lack sensory feedback.

In order to perform delicate tasks like folding a sheet or testing the ripeness of a plum, you need to be able to feel those objects and react accordingly. 

How does it work?

To make that happen, the researchers implanted electrodes into the nerves on Walgamott's forearm, allowing his brain to communicate with his prosthetic through a computer outside his body. That means he can move the hand just by thinking about it.

But those signals also work in reverse. 

The team attached sensors to the hand of a LUKE Arm. Those sensors detect touch and positioning, and send that information to the electrodes so it can be interpreted by the brain.

Biomedical engineering graduate student Jacob George, left, and associate professor Greg Clark, right, tinker with the LUKE Arm. (Dan Hixson/University of Utah College of Engineering)

"We changed the way we are sending that information to the brain so that it matches the human body. And by matching the human body, we were able to see improved benefits," biomedical engineering professor Gregory Clark, the study's lead author, said in a press release.

"We're making more biologically realistic signals."

What's next?

For Walgamott, performing a series of menial tasks as a team of scientists recorded his progress was "fun to do."

"I'd forgotten how well two hands work," he said. "That was pretty cool."

 

But it was also a huge relief from the phantom limb pain he has experienced since the accident, which he describes as a "burning sensation" in the place where his hand used to be.

"It's there constantly and sometimes it'll wake me up at night," he said. "It never goes away."

That is, until he used the LUKE Arm.

"My phantom pain almost went to zero during the tests," he said. "It was wonderful not to have that."

That relief lasted for about an hour after each experiment, he said.

Clark said that he's hoping some of the test subjects will be able to take the prosthetic home in 2020 or 2021, pending federal approval.

Meanwhile, the team is working to develop a mobile version of the technology, so people like Walgamott won't have to be attached to a computer to use it. 

"I would think within my lifetime I would probably see one of these that would be unavailable at a price that we could afford," Walgamott said.

"I'm much more hopeful now than I used to be that I would be able to see the results of it."

The research was conducted by multiple departments at the University of Utah in collaboration with the University of Chicago, the Cleveland Clinic, Ripple Neuro LLC and Blackrock Microsystems with funding from the U.S. Defense Advanced Research Projects Agency and the National Science Foundation.

Written by Sheena Goodyear. Produced by Katie Geleff. 

Comments

To encourage thoughtful and respectful conversations, first and last names will appear with each submission to CBC/Radio-Canada's online communities (except in children and youth-oriented communities). Pseudonyms will no longer be permitted.

By submitting a comment, you accept that CBC has the right to reproduce and publish that comment in whole or in part, in any manner CBC chooses. Please note that CBC does not endorse the opinions expressed in comments. Comments on this story are moderated according to our Submission Guidelines. Comments are welcome while open. We reserve the right to close comments at any time.