Flexible, multi-functional spinal implant capable of restoring mobility after paralysis also harvests information about brain signals that could have a significant impact on the way we understand and treat physical disabilities.
Stories of making the disabled walk again have been told for millennia. It’s the stuff of miracles and Hollywood movies. It’s also a significant challenge for scientists around the world.
1 in 50 Americans live with paralysis, according to a study from the Christopher & Dana Reeve Foundation. Leading causes of paralysis include stroke, multiple sclerosis, and spinal cord injuries. The prevalence of these potentially paralyzing illnesses or injuries is significant. This is especially true for strokes, which affect 1 in 6 people worldwide, according to the World Stroke Campaign.
e-Dura: The Next Generation Spinal Implant
Researchers have been working on a way to bridge an injured spinal cord—to re-route neural messages and enable movement in paralyzed patients. Innovative scientists have been getting close to a workable implanted bridge for years, but have been unable to develop a bridge that can be implanted on the spine or brain for an extended period of time.
Previously developed implants were rigid and rubbed against the surrounding tissue as they moved in a host. This led to irritation and inflammation, in addition to further nerve damage. Ultimately, the rubbing triggered rejection by the host.
Swiss scientists, led by professors Stéphanie Lacour and Grégoire Courtine from Ecole Polythechnique Fédérale de Lausanne, have developed a stretchable implant. Their e-Dura prototype slips into the spinal cord and enables paralyzed rats to learn to walk again using a combination of electrical and chemical stimulation.
e-Dura is a soft neural implant with the shape and elasticity of dura mater, the protective membrane of the brain and spinal cord. It stimulates the spinal cord at the injury site.
The size of a small bandage, the Swiss prototype closely imitates the mechanical properties of living tissue, and serves a dual-function: it can send electric impulses and medications simultaneously. The drug-releasing component is capable of reanimating nerve cells by delivering neuro-transmitting drugs directly to the injured tissue.
This innovation is unique because it is “soft and stretchable, just like the surrounding tissue,” according to Lacour.
e-Dura dramatically reduces the risk of rejection or further nerve damage. In rat testing, the prototype was implanted for two months and the animals did not sustain nerve damage or reject it.
"Our e-Dura implant can remain for a long period of time on the spinal cord or the cortex, precisely because it has the same mechanical properties as the dura mater itself. This opens up new therapeutic possibilities for patients suffering from neurological trauma or disorders, particularly individuals who have become paralyzed following spinal cord injury," explains Lacour.
Harvesting Data for Improved Rehabilitation
The e-Dura implant also allows for real-time monitoring of electrical impulses from the brain. Scientists were able to know exactly what the animal’s motor intentions were before those intentions were translated into movement.
Notably, implanting the e-Dura did not instantly cause the rats to rise up and walk. The rats received mechanical physical therapy, which allowed them to regain the ability to walk on their own after only a few weeks of training.
While further research is needed here, this could have a significant impact on physical therapy and rehabilitation. The information could certainly inform a single patient’s rehabilitation process. However, there could be the potential to access and share this data with other caregivers to gain new insights into recovery.
To date, the e-Dura implant has only been tested on rats. The team is moving toward clinical trials in humans this year and plans to further develop the prototype for commercialization.
The potential for applying these surface implants is significant, and not just for the treatment of paralysis. It could offer new ways of treating epilepsy, Parkinson's disease and pain management.
Jenn Lonzer has a B.A. in English from Cleveland State University and an M.A. in Health Communication from Johns Hopkins University. Passionate about access to care and social justice issues, Jenn writes on global digital health developments, research, and trends. Follow Jenn on Twitter @jnnprater3.