Wireless brain-spine 'digital bridge' allows paralyzed patient to walk

Spinal cord injury patient Gert-Jan Oksam standing at a bar for drinks with friends while wearing experimental "digital bridge" technology to send leg control signals from his brain to his spine.

“This simple pleasure represents a significant change in my life,” Gert-Jan Oksam said of his regained ability to stand at a bar with friends thanks to an experimental “digital bridge” between his brain and spine. [Photo courtesy of NeuroRestore]

A wireless “digital bridge” between a paralyzed patient’s brain and spinal cord has allowed him to walk naturally, researchers say.

The experimental technology uses electronic implants on the brain and spinal cord to relay leg movement control signals, allowing 40-year-old Gert-Jan Oksam to walk again 12 years after a bicycle accident.

Neuroscientists and neurosurgeons from Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne University Hospital (CHUV) and University of Lausanne (UNIL) published their research in Nature last week.

“We have implanted Wimagine devices above the region of the brain that is responsible for controlling leg movements,” neurosurgeon Jocelyne Bloch explained in a news release. “These devices … decode the electrical signals generated by the brain when we think about walking. We also positioned a neurostimulator connected to an electrode array over the region of the spinal cord that controls leg movement.”

Bloch and Grégoire Courtine, a neuroscience professor at EPFL, CHUV and UNIL, led the project through NeuroRestore, a EPFL and CHUV research and innovation center focused on restoring neurological functions through medical therapies.

Previously: Paralyzed patients walk, swim and cycle with spinal cord neuromodulation implant

Implants and algorithms made ‘digital bridge’ possible

Wimagine brain implants monitor brain activity. [Photo courtesy of NeuroRestore]

Developed by the French Alternative Energies and Atomic Energy Commission (CEA), the implantable Wimagine brain device previously allowed a tetraplegic patient to control an exoskeleton.

“Thanks to algorithms based on adaptive artificial intelligence methods, movement intentions are decoded in real-time from brain recordings,” said Guillaume Charvet, head of the brain-computer interface (BCI) program at CEA.

The new system converts movement intentions from the brain into electrical stimulation sequences on the spinal cord to activate leg muscles as desired. This wireless digital bridge from the brain to electrodes placed on the part of the spinal cord that controls leg movements bypasses the injured part of the spinal cord.

Oksam can now stand, walk, climb stairs — and enjoy a beer with friends at a bar while on his own two feet.

“This simple pleasure represents a significant change in my life,” Oksam said in the news release.

An illustration showing brain implants monitoring motor cortex activity.

The Wimagine brain implants monitor activity in the regions responsible for leg movement. [Photo courtesy of NeuroRestore]

After the surgeries to implant the devices in the brain and on the spine, Oksam needed to learn how to use his legs again, but said it was a faster process than he expected.

“The most surprising thing I think happened after two days,” Oksam said in the video below. “Within five to ten minutes, I could control my hips — the brain implant picked up what I was doing with my hips.”

The researchers said they could measure “remarkable improvements” in Oksam’s sensory perceptions and motor skills even when the digital bridge was turned off, suggesting new nerve connections may have developed.

Onward: The next steps

An illustration showing an electrode placed on the spinal cord for stimulation.

The neurostimulator delivers electrical signals via an electrode array placed on the spinal cord. [Photo courtesy of NeuroRestore]

Oksam is the first and only patient to “test pilot” the technology so far. But the researchers said the digital bridge approach between brain and spine could be used to restore arm and hand movements for spinal cord injury patients, or to treat paralysis due to stroke.

The European Commission’s European Innovation Council is supporting commercial development of the technology through CEA, EPFL and medtech developer Onward Medical.

Led by former Medtronic executive Dave Marver as CEO, Onward Medical makes external and implantable stimulation systems, including the implantable ARC-IM lead used in Oksam’s therapy. The company designed ARC-IM specifically to help spinal cord injury (SCI) patients regain movement and function.

“This publication shows the remarkable potential of ARC Therapy to be enhanced with the introduction of a BCI, facilitating more natural movement based on the thoughts of a person living with paralysis,” Marver said about the research project. “We have positioned Onward as a leader in the BCI field with our unique understanding of spinal cord stimulation for people with SCI.”

Onward Medical is headquartered in the Netherlands and said it also has a growing U.S. team in Boston. The company has won nine FDA breakthrough device designations. The most recent was for its ARC-IM therapy for spasticity in people with SCI. Onward is also exploring ARC-IM for improved blood pressure management, mobility, upper extremity function, and bladder control.

Onward expects to start commercializing its products with the launch of its external ARC-EX as soon as this year or early next year, pending FDA de novo clearance for an upper limb indication.