Exoskeleton Helps Paralyzed Patients Walk
Exoskeletons find their way to hospitals, helping people with spinal injuries.
Exoskeletons have been designed for military use and boosting strength. But the same technology that makes people able to lift heavier loads might also one day allow those with spinal injuries to walk.
Ekso Bionics, a California company, developed the Human Universal Load Carrier, or HULC, a military exoskeleton licensed to Lockheed-Martin (at that time the company was known as Berkeley Bionics). Ekso developed another exoskeleton, also called the Ekso, for people who need either physical therapy or rehabilitation. Other exoskeletons have been built for arm movement; this is among the first to help people move their legs and to be commercialized in the United States (another type, called Rex, is available in New Zealand, but it works on different principles).
Amanda Boxtel is one of those people. Her legs were paralyzed after a skiing accident in 1992, at the age of 24. "I never thought I would walk again," she said today at a press event in New York City. Now she practices walking with the Ekso. Demonstrating it, Boxtel was able to take steps, and even turn around, if slowly. Even though she was assisted by engineer Thomas Dwyer, who controlled it using a small game-controller-like device,it showed the possibilities.
The Ekso is currently used in hospitals and physical therapy centers. Right now it offers more natural movement to people who might need help rebuilding muscles after an injury, or relearning to walk after a stroke. It can't walk backwards or climb stairs, though.
That will change in future iterations. Within two years, said Mike Magill, sales and marketing consultant to Ekso, there will be a model for the home - slimmer, lighter, and able to move in all the ways that humans ordinarily do. "It should be as easy as putting on a pair of jeans," he said.
For a person to walk, the Ekso has to look at where their weight is, as well as check how the leg is bent and the location of the other leg. If certain conditions are satisfied, it takes the next step. Dwyer said a person can walk by just shifting her weight. At present the exoskeleton needs to be used with crutches, but as the system is refined, they will become unnecessary, he added.
One thing that's different from the HULC (see a video here of the Science behind the HULC) is the kind of power the motors use and how much they need. The HULC uses hydraulic systems for extra strength and requires a lot more power. The Ekso uses smaller electric motors and is powered by what is essentially a laptop battery (if a bit more powerful). It doesn't need to lift hundreds of pounds in addition to the user, so it can be made smaller and slimmer. Eventually, the company also hopes to make one that can be easily taken on and off and is small enough to wear.
Beyond walking, there are also therapeutic benefits. When the legs move circulation is better, and it can help patients who might recover use of their limbs to exercise as part of their therapy.
Boxtel said she can't wait to get one. One big reason: plane rides. Wheelchair users can't bring their chairs onto a plane because the aisles are too narrow. So they have to wait for the crew to get them a special chair to get them out. "I don't know how many times I've been left there, forgotten," she said.
Beyond that, there are therapeutic benefits. Boxtel said when she uses it the circulation in her legs gets better, and with it her overall health. She also likes being able to stand. "For the first time in twenty years, I can see people at their level."
Photo: Amanda Boxtel and Thomas Dwyer demonstrate the Ekso.
Credit: Jesse Emspak