'This is not a magic wand': Spinal stimulation used on Humboldt Bronco promising but in early research stages

Recent videofrom Thailand showing paralyzed Humboldt Broncos hockey player Ryan Straschnitzkimoving his legs after an electrical stimulation device was surgically implanted in his spine has sparkedexcitement as well as questions about therapies available to Canadians with spinal injuries.

The procedure Straschnitzki, 20,had is called epidural stimulation,and although promising, it's still highly experimental, experts in both Canada and the U.S. say. It's in early stages of clinical trials in the U.S. and Europeto evaluate the safety and effectiveness of restoring physical abilities from bowel and bladder function to moving arms and legs to people who desperately want to get some normalcy back after spinal injury.

Barry Munro understands all too well why people's immediate reaction is to ask why they can't try the procedure here in Canada. He's been hoping for and working toward finding a cure for spinal cord injuryever since he dove into a lake in his 20s and was left quadriplegic.

Now 55, Munro is chief development officer for the Canadian Spinal Research Organizationand works with the North American Spinal Injury Consortium. For more than 30 years, he's seen the headlines come and go, inciting hope that a cure is on the horizon.

"I've been down this road before," Munro told CBC News."Ireally, really believe in finding a cure and believe it will happen and I have that hope. But there's a big but we have to be careful."

MilosPopovich, director of the KITE Research Institute at the University Health Network's Toronto Rehabilitation Institute, echoes that need to proceed with caution. He saidthat epidural stimulation must proceed through many more stages of scientifically soundclinical trials to prove it works before it could be made available as a therapy in Canada.

"This is not a magic wand," Popovich said.

Although both Popovich and Munro want to protect people from false hope, they also say epidural stimulation is a significant area of spinal cord research. It's important, they say, for people to know the facts and understand that it's still early days.

What is epidural stimulation?

Epidural stimulation involves sending electrical impulses into the spine and was actually developed many years ago as a treatment for people suffering fromexcruciating pain.Researchers later discovered that in some patients with spinal cord injuries, the electrical impulses stimulating the nerves also appeared to be generating movement.

Epidural stimulation requires surgery to place electrodes on the surface of the dura, the tissue that wraps around the spinal cord. The surgeons connect those electrodes to a device called an implantable pulse generator (IPG) that is placed elsewhere in the body, often inthe patient's lower back.

Researchers canthen start and control the electrical stimulationfrom a computer that sends wireless signals to the implantable pulse generator, which in turn stimulates the electrodes.

The idea, in very basic terms, is to stimulate neurons.Researchers sayit's important to understand that the movementgenerated during epidural stimulation lasts only while the device is turned on.Participants in epidural stimulation studies alsodomany hours of intense physical therapy.

"It's not justflipping a light switch," saidPeter Grahn, a neuroscientist at the Mayo Clinic in Rochester, Minnesota, who has been conducting clinical trials on epidural stimulation.

In a previous studywith two participants, Grahn and his colleagueswere able to get them standing without the assistance of atherapist while the epidural stimulation device was turned on.

Grahnhimself wasparalyzed in by a spinal cord injury in 2005, and is excited about the possibilities epidural stimulation may present. But at the same time, he said,"there's a lot of work that needs to be done on the scientific side" to better understandthe specific biology and mechanics at play.

Is epidural stimulation the only potential therapy?

No. In fact, the next step in Grahn's work is a larger clinical trial that launched earlier this year, comparing epidural stimulation with another potential therapy that also attempts to stimulate the nerves in the spine, but is much less invasive. It'scalled transcutaneous stimulation (sometimes referred to as surface stimulation) and the device is placed on the skin overthe spine, rather than being surgically implanted.

Canadaalso appears to be much closer to getting a clinical trial in transcutaneous stimulation than epidural stimulation. Popovich saidthe University Health Network's Toronto Rehabilitation Instituteis considering starting a study examining whether transcuteneous stimulation can create upper limb movement.Like epidural stimulation, transcutaneousstimulation is also experimental and in the early stages of clinical trials to assess safety and effectiveness.

Why is it taking so long?

A significantchallenge in spinal cord stimulation is the sheer number of neurons controlling so many different functions of the body, said Milos Popovich of the Toronto Rehabilitation Institute.

Scientists are still learning how to targetthe right neurons to get the desired effect (e.g., movement of a leg) but they also don't want to accidentally create any undesired effects.

"There's always a drive to try to translate [research] to the clinic as fast as we can, but there's also the aspect of [doing it] as safely as we can," said Grahn at the Mayo Clinic."It's a balancing act."

"The worst thing that could happen right now is if somebodywere to use the device inappropriately or incorrectly," he said. "And then it sets the whole entire field back because then there's more regulatory scrutiny and everything on these devices because somebody got hurt."

What are the risks?

In the case of epidural stimulation, even the surgery poses a risk.

Spinal injury not only paralyzes people's legs, arms, or both, but can also leave them with other lifelong serious health issues, such as higher susceptibility to infection or compromised lung capacity that can make surgery more dangerous.

Electrical stimulation in people with spinal cord injuries also carries potential unintended consequencesthat researchers conducting clinical trials need to watch out for, said Grahn.

After injury, the spinal cord no longer communicateswhen something is wrong and hence the spinal circuitry can "almost go a little bit haywire," he said.

So if the nerves are being stimulated in the wrong way and something dangerous is happening such as fluctuations in blood pressure orheart rate the spinal cord may not send a signal to the brain that something is amiss and needs to be regulated. Thatmakesit especially important for researchers to carefully monitor these vital signsduringelectrical stimulation, he said.

Is electrical stimulation just about helping people to walk again?

Walking again is a dream for most people with spinal cord injury,but there are other physical abilities that are even more important to many people that the public often don't think about, said Barry Munro of theCanadian Spinal Research Organization.

Moving arms and hands, bladder and bowel control, as well as sexual functionare also areas researchers are looking to improve withthe electrical stimulation.

What does the future look like for spinal injury cures or treatment?

Even thoughit may be frustrating for people to hear that these therapies are still in the experimental phase, it's important to remember that spinal injury research has made important strides over the past decades, Munro said.

"Has it moved quick enough? I don't think so," Munro said.

"[But] we're talking clinical trials.I remember the day wherethat was science fiction. So we have moved the bar."

What's most important now, Munro said, is for researchers across North America and the world to communicate with each other, as well as withpeople actually living with spinal cord injuries.

As part of that process, it's vital for people with spinal cord injuries to have access to reputable clinical trials they can learn about and possibly participate in, Munro said. His organization recommends a new website launched recently called SCITrials.org, which provides links to clinical trials specifically devoted to spinal cord therapies.

Clinical trials are moving forward not only in epidural stimulation and transcutaneous stimulation, but also in stem cell therapiesand neuroplasticity, which uses activity-based rehabilitation to try to train the neurons and muscles to work around the spinal damage.

"I'm excited about this," Munrosaid. "The future is going to be a combination of therapies for a cure."