From
Discovery News. In the picture, Roseann Sdoia, a Boston Marathon bombing survivor, tries out a new leg at Next Step Bionics, Inc. in Newton, Mass.
When bombs rocked the Boston Marathon last year, emotional
reverberations were felt throughout the country: Communities held
memorial races and sported Boston Strong ribbons and shirts, created
makeshift memorials out of running shoes and American flags, donated
money to families of injured runners. Engineers, meanwhile, got down to
the nitty-gritty: Building better prosthetics for the 16 survivors who
lost limbs that day.
"I think Boston raised awareness and is kind of inspiring for
promoting recovery instead of focusing on the injuries," said Levi
Hargrove, Director of the Neural Engineering for Prosthetics and
Orthotics Laboratory at the Rehabilitation Institute of Chicago. Even
though his lab hasn't worked directly with survivors, everyone in the
field has felt the impact, he said.
"The survivors are getting back to their lives, working with
scientists and therapists, because they're going to be living with this
condition for a long time," Hargrove said.
Last month, one of those survivors took the stage at TED2014
and showed off her first-of-its-kind bionic leg that allows the
professional ballroom dancer to rumba again. After Adrianne Haslet-Davis
danced, she tearfully thanked Hugh Herr, director of the Biomechatronics Group at The MIT Media Lab and creator of the leg.
"All this emotion poured out," Herr said. "The very first time
she [tried the new leg], she was ecstatic. She was so joyful about being
on that dance floor and feeling that freedom again."
Herr, whose lab partnered on a fund
to support the development of specialized prostheses for runners after
the Boston attack, based Haslet-Davis's leg on data he gathered from
dancers of a similar build and body type to Haslet-Davis's. He invited
the dancers to his lab, which was tricked out with sensors to track
exactly how they moved and how their forces impacted the dance floor.
The idea, he said, was to extract those principles of dance and imbed them into chips on the bionic limb.
"It's responsive in a way that's appropriate biomechanically,"
he said. "It doesn't simply output a traditional trajectory that she
would have to keep up with like a wind-up toy. It's more like she is the
lead and the limb is the partner."
The leg also has to be able to move like flesh and bone, so the
lab uses a "smart" material that can flop and stiffen depending on the
voltage being applied from the body.
David Sengeh, a graduate students who also works in Herr's lab,
recently won the Lemelson-MIT National Collegiate Student Prize
Competition for his work on improving the sockets used in prosthetics.
Conventional molding methods often result in prostheses that don't fit
precisely, and often cause pain. Sengeh uses MRI and a 3D printer to
create a design interface based on individual data.
"The goal is to make a model where you can enter someone's
data, press play and get a comfortable socket," said Sengeh, who tested
the method on one of the Boston survivors.
The end result? Without the short skirt she wore at her TED
performance to show off the leg, it may have been impossible to tell she
wasn't born with that leg.
