Blade Runners: Future Of Prosthetics


BOULDER, Colo. (Ivanhoe Newswire) — They are called blade runners, elite athletes who are among the fastest in the world. The fastest running with only one or even no legs and they are among the first to break records with a new generation of prosthetics.

Running faster, stronger, longer … that’s what brings Alex Klein, LSU Student, and Jessica Heims, Paralympic Track & Field, to CU Boulder and Alena Grabowski.

(Read Full Interview)

Heims said, “I had a little baby foot, but that was amputated when I was a year old.”

Klein shared, “I had cancer when I was eight.”

Grabowski is helping these amputees sprint onto the world stage.

Grabowski said, “We’re at a place right now where athletes are very high caliber and they’re working extremely hard to be able to compete at the highest levels and I’m hoping that we can start to keep up with them.”

She is focused on optimizing a prosthetics stiffness, height, weight, shape: “How they move, how they walk, run, sprint, hop, jump,” explained Grabowski.

Today they’re using cameras and sensors to measure how these sprinters move, track their force, and test these new carbon fiber blades.

Eric Kirby said, “By changing, enlarging this curve and adding the compound curvature here, that gives you more snap and response.”

“I think something like that is going to work better around curves,” said Grabowski.

Heims said, “I’m on a sprinting blade which when I jog on it, it feels different because it’s thicker.”

Kirby explained, “What we’re seeing today is that this, by splitting the blade, it gives you more ground on ground contact.”

In this video, world class sprinter Blake Leeper, born without legs, is leading the way. He is being called the fastest human on earth and in Grabowski’s lab was clocked at about 25 miles per hour. And she believes this is just the beginning. Giving young sprinters around the world a chance to compete against the best in the world.

“I don’t feel like anything is holding me back. I feel like I can do whatever whenever I want,” Klein said.

Heims shared, “That first day I felt like I could just run forever and never stop.”

It’s still to be decided if amputees like Blake Leeper will be allowed to run in the 2020 Olympics in Tokyo. The International Association of Athletics Federations banned amputees from running against other runners after a German study concluded that blades allowed the runner to expend 25 percent less energy, even though researchers at Rice University concluded that was false, stating that blades put the runners at a disadvantage because they pushed off with less force than a biological limb would.

Contributors to this news report include: Marsha Lewis, Field Producer; Rusty Reed, Videographer; Cyndy McGrath, Supervising Producer; Jamison Kozcan, Editor.

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REPORT:       MB #4663

BACKGROUND: Prosthetics designed for athletes have a 40 year legacy. These ingenious “blade” prosthetics shied away from earlier heavy designs and focused on the mechanics of muscle movement. Their invention spurred an athletic renaissance in which amputees run competitive distances, climb mountains, and downhill ski. Running blades were invented by American inventor Van Phillips, who lost his lower leg in a water- skiing accident in 1976. Depressed by the limited athletic function of prosthetics at the time, he enrolled as a student at Northwestern University Medical School’s Prosthetic-Orthotic Center. He quickly recognized that while most prosthetics tried to mimic human bones, he could focus on replicating ligaments and tendons. He came up with the idea for running blades by observing animals like kangaroos and cheetahs, as well as the mechanics of diving boards and pole vaulting. The result was Flex-Foot – his model of carbon fiber blade prosthetics and the name of his company. His contribution to the history of prosthetic legs has inspired generations of athletic amputees.


CARE: A prosthesis can be particularly subject to perspiration as it is enclosed in a plastic socket. This can be a source of odor and bacteria, as well as the culprit behind skin problems. Sprinkling the residual limb with baking soda, or if needed, apply an over-the-counter antiperspirant such as CertainDri may help. The more consistently the prosthesis is worn, the more the residual limb will adjust to being inside the socket, with perspiration naturally subsiding. It’s important to keep a good supply of prosthetic socks on hand. Swelling and volume fluctuation may occur but a shrinker sock is useful to reduce swelling and should be worn when you are not wearing your prosthesis.


NEW RESEARCH: Alena Grabowski, PhD, Biomechanics at CU Boulder talked about the hurdles for developing better a better prosthesis, “Running’s a little bit trickier than walking because it’s so much faster. So if I were to try to design a running-specific prostheses that would enhance running, it would be something that had a very lightweight motor, something that allowed very quick feedback, something that was actually connected to the person so the person could actually drive that prosthesis, not just react to it. And so, there’s a lot of aspects that would have to be perfect to really make that prosthesis work the best.”

(Source: Alena Grabowski, PhD)


Lisa Marshall


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Doctor Q and A

Read the entire Doctor Q&A for Alena Grabowski, PhD, Biomechanics

Read the entire Q&A