Getting back on your feet one step at a time

Hopes are raised regularly via the media that paraplegics will soon be able to walk again thanks to scientific advances, but Swiss researchers warn that developments will take time, and are moving ahead only slowly.

Hopes are raised regularly via the media that paraplegics will soon be able to walk again thanks to scientific advances, but Swiss researchers warn that developments will take time, and are moving ahead only slowly.

Look around and you will certainly find reports about paraplegics getting around thanks to so-called exoskeletons. Last year, Claire Lomas finished the London marathon wearing a bionic suit, albeit 16 days after the race began.
 
The electronic gear helping her along was worth £43,000 (CHF63,000 at the time) – and cost is one of the main drawbacks of this kind of robotic equipment. Systems of this type are extremely expensive, and depending on how your condition came about, out of reach for most Swiss patients. 
 
If the disability is the result of illness, the public disability insurance only has an obligation to ensure that “simple and adequate” measures are taken to help the patient. If paralysis is the result of an accident, a different kind of insurance kicks in and the outcome might be more positive.
 
Robotic systems don’t provide a one-size-fits-all solution either. What works for one patient might not for another (see video).  
So the race is on to find therapeutic solutions that are hopefully less costly and simpler to implement.
 
“There really is a quest to be the first to discover the best therapy,” says Grégoire Courtine, a brain researcher at Lausanne’s Federal Institute of Technology (EPFL). “It’s a very difficult field to work in because everyone thinks they have the solution and that the others don’t understand anything.”

Making headlines

Courtine’s work hit the headlines last year, featuring notably in the New York Times and on CNN. His research, published in Science, showed that totally paralysed rats with spinal cord lesions could  “learn” to walk again, attracting interest from around the world.
 
After a few weeks of neurorehabilitation using a treadmill, a robotic harness, electric and chemical stimulation, the rats were sprinting, climbing up stairs, and avoiding obstacles.
 
Despite the media hype, Courtine is at pains to explain that what he and his team have developed is not a cure.
 
“If people were able to take a few steps, with the help of a walker, that’s probably the most we can expect,” he told swissinfo.ch. “But patients say to me that would be wonderful, that their lives would be so different.”
 
“That is my goal: that people can say that their lives are better because of the work we did. But we won’t be seeing people sprinting down the street again, that would utopic.”
 
Courtine aims to develop an ambitious system that combines stretchable spinal electrode arrays, drugs and robotic rehabilitation, but he is not rushing headlong into development.
 
“We are […] moving forward in a systematic manner. This means I do not want to jump [straight] from rats to humans given, for example, potentially unsafe effects of pharmacology.”
 
First clinical trials of the electrodes could start later this year, along with the robotic system that is currently being developed by an unnamed firm.
 
The pharmaceuticals, which are already approved for other applications in humans, will have to wait a little longer. Because they have to be injected near the spinal cord lesion, the first thing is to check the drugs for neurotoxicity using non-human primates.
 
“We hope in three to five years’ time we will be able to include pharmaceuticals in testing patients as early as possible after they suffer a lesion,” says Courtine. “The big question is if the drugs will be effective in humans.”

Helping stroke victims

A first glance, Ability, a Zurich-based start-up, is less ambitious. It is developing a system designed to replace the treadmills used to help rehabilitate stroke victims and train them to walk again.
 
“There are 15,000 stroke survivors in Switzerland alone every year,” points out Ability’s young CEO Cornel Stuecheli. “We have chosen to focus on these patients first and will let physicians suggest other applications.”
 
The company’s system, based on a natural walking motion and focusing on one particular action, remains tightly under wraps and is backed by private investors. A major advantage of its design is that it would help cut down on the number of people involved in a rehabilitation session, which is up to three therapists for one patient.
 
Like Courtine’s research it relies to some extent on the brain and nervous system’s capacity to “rewire” itself, so-called plasticity, with some stimulation.
 
However, the Ability system can cut the brain itself out of the equation, instead focusing on the fact that some motor functions do not need grey matter to function properly – think of headless chickens running around – and can be learnt again.
 
Development has been slow, but Stuecheli says factors such as ease and safety of use and avoiding over-engineering have been high on the company’s priority list. “The device, like the human body, has to be optimised for its function, in other words it must have an inherent efficiency,” he added.
 
The CEO is convinced the end result will be better than using devices such as exoskeletons, but as a businessman he also admits that cost will also be a deciding factor for potential clients, especially clinics trying to attract customers.
 
“Physicians, providers and patients have to consider this to be a winning solution for it to work,” he said. “However, the neurorehabilitation market is growing fast because clinics are prepared to invest.”
 
Initial feedback has been positive enough to look beyond the clinical environment. Ability’s apparatus could also be further optimised for outpatient therapy.
 
At the end of the day, Courtine and Stuecheli have the same stated goal, getting people back on their feet at least part of the time.
 
“Getting out of the wheelchair and regaining autonomy is critical for patients,” says Stuecheli. “What’s important is being able to care for yourself.”

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