For most people, powered exoskeletons are the stuff of movies such as “Starship Troopers,” “The Avengers,” and its most famous embodiment, “Iron Man.”

However, for people with spinal cord or stroke-related injuries, exoskeleton technology provides an opportunity to rehabilitate and potentially walk again.

About 375,000 people worldwide sustain spinal cord injuries each year, and strokes occur in about 17 million people.

Some of these patients are prescribed a rehabilitation plan that uses exoskeletons to help perform tasks based on specific needs.

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From Robots to Exoskeletons

Technology has always played a role in physical therapy.

Robotics, in some form or another, has been around for decades.

Exoskeletons emerged on the scene about five years ago, according to Arun Jayaraman, Ph.D., P.T., who leads the Rehabilitation Institute of Chicago Max Näder Lab for Rehabilitation Technologies and Outcomes Research.

Today the devices are used in numerous ways.

They can augment a specific joint that needs rehab such as the hip, ankle, or knee.

Exoskeletons can also provide full-fledged mobility to people who can’t walk or need to learn how to walk again.

Jayaraman says that for patients with severe immobility, the technology shows great promise that traditional therapy can’t provide.

For example, people with stroke and spinal cord injuries tend to plateau after months of therapy sessions.

It’s a critical juncture, he adds, because secondary health issues such as bedsores and diabetes may develop.

“The robots can lift and move patients and get them to a level of exercising which can help prevent long-term health issues,” Jayaraman told Healthline.

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What’s It Like?

So what does it feel like to walk around in an exoskeleton suit?

“It’s more like ice-skating than walking. Like a waltz, with a swing,” Michael Patrick Thornton told Healthline. “It doesn’t hurt. It’s very lightweight and comfortable.”

The Chicago-based actor and founder of The Gift Theatre Company is using an exoskeleton on stage right now while playing the lead in “Richard III.”

In 2003, Thornton suffered a spinal stroke that left him paralyzed. After much therapy he regained some movement in his upper body, but Thornton still uses a wheelchair to get around.

Except when he is onstage this spring.

He said the only real challenge about using the “exo,” as he calls it, is to simultaneously walk in the apparatus and recite the enormous amount of dialogue in the Shakespearean play.

“It’s a lot of balls in the air,” he said, with a chuckle.

But he doesn’t mind. Thornton said the device elicits a range of emotion from audience members. And once the play is over, those feelings are likely to spark a dialogue about the role of disabled people in society.

“I think it’s a great Trojan horse to usher in these initial conversations,” he said.

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New Devices Appearing

Just this month, Ekso Bionics, based out of Richmond, California, received approval from the U.S. Food and Drug Administration (FDA) for the use of its Ekso GT in the rehabilitation of patients with spinal cord and stroke-related injuries.

The device is now part of a small group that has FDA approval for clinical use. This includes devices created by ReWalk Robotics, based out of Massachusetts and Indego, owned by Parker Hannifin.

Exoskeletons are powered through a series of gears controlled by sensors and highly intelligent software. While the fundamentals of the technology remain constant, the components and focus vary slightly when comparing manufacturers.

Ekso Bionics only develops products for rehab purposes. The Ekso GT is the first of its kind to receive a federal nod for stroke rehabilitation.

The suit takes only a few minutes for patients to put on and take off. Plus, its software allows physical therapists to make on-the-spot adjustments during a therapy session based on system feedback.

“We monitor the effort a person can put into a step, 500 times a second,” Thomas Looby, president and interim CEO of Ekso Bionics, told Healthline. “Sensors are all over the feet and joints.”

Other companies such as SuitX develop products that provide aid in the workplace. SuitX’s only piece designed for rehab is called The Phoenix.

At 27 pounds, it’s one of lightest around. The founder, Dr. Homayoon Kazerooni, embraces a minimalistic approach in order to keep costs down and improve accessibility.

“We have this incredibly clever software that controls the hip, such that the knee goes into the right angle,” he said.

Kazerooni is a professor at the University of California at Berkeley and was also the founder of Ekso Bionics. He left that company in 2010.

The Phoenix does not have FDA approval yet, but Kazerooni hopes to get the green light by next year.

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A Cold War Inspiration

Exoskeletons were first mentioned in science fiction works in the 1860s.

Today’s technology stems from the Cold War with the Soviet Union after World War II and the drive to build a faster, stronger soldier.

The earliest suit weighed upward of 1,500 pounds.

It wasn’t until the 1980s and 1990s, when complicated computer algorithms emerged that allowed researchers to scale the machines in a way that hadn’t been possible.

The current devices are the smallest to date.

Exoskeletons have come a long way from their first version, but Jayaraman adds that the industry is still in its infancy.

“These robots are in the baby phase,” he said. “They are like your old giant cell phone.”

In about 10 years exoskeletons will be so small, people won’t know if a person is wearing one, he noted.

“They will have smart coaches inside and teach you how to exercise,” Jayaraman said. “You can be the therapist at home.”