How two implants are helping a paralyzed man walk again

In 2011, Gert-Jan Oksam was left paralyzed from the hips down after a motorcycle accident. In the years after, Oksam underwent several stimulation procedures, including one for an experimental spinal cord stimulator in 2017.

Although this spinal cord stimulator helped restore his ability to walk, he could only take steps if he was in sync with the stimulator's rhythm, something he found stressful. Oksam also noted that there "was something foreign about the locomotion, an alien distance between his mind and body" when he used the stimulator, the  New York Times reports.

However, a new experimental technology, which combines both a brain implant and a spinal implant, has allowed Oksam to take more control of his movements and walk more naturally than before.

In 2021, Oksam underwent an operation to insert two disc-shaped implants above the regions of the brain that control movement. These implants wirelessly transmit his brain signals to two sensors on a helmet.

He also had an operation to insert a second implant to nerve endings related to walking around his spinal cord. To connect both implants together, researchers developed an artificial intelligence program that would translate electrical signals from Oksam's brain to the spinal implant, which would then send electrical signals to different parts of his body to create movement.

After a few weeks of training with the implants, Oksam could stand and walk while using a walker. As he used the implants more and more, he began to regain more abilities. More than a year later, Oksam can now pause in his steps, adjust his stride, and walk on irregular terrain, including stairs, although only for limited amounts of time. He can also take a few steps with crutches even when the implants are turned off, suggesting that he has experienced some neurological recovery.

"For 12 years I've been trying to get back my feet," Oksam said. "Now I have learned how to walk normal, natural."

"It has been a long journey, but now I can stand up and have a beer with my friend," he added. "It's a pleasure that many people don't realise."

"It was quite science fiction at the very beginning but it became true today," said Jocelyne Block, a neurosurgeon at the University of Lausanne in Switzerland who performed Oksam's surgeries.

What are the next steps with the technology?

According to Peter Grahn, an engineer in Mayo Clinic's department of neurologic surgery, the technology's ability to stimulate both the brain and spinal cord essentially in real time is "impressive."

"That's something nobody's achieved before," Grahn said. And while the same group of researchers had shown similar results in monkeys before, "this is way above and beyond that." With this new development, the field of paralysis treatments will "move faster and with more confidence," he said.

Grégoire Courtine, a spinal cord specialist at the Swiss Federal Institute of Technology, Lausanne, who helped lead the research, said that while "[t]he technology is still in its infancy, … it is tremendous technology."

Currently, the research team is working on downsizing the hardware needed to run the implants, which Oksam carries with him in a backpack.

The team also hopes to launch a clinical trial of the technology in roughly a year. The trial will likely take place in the United States where stimulators have not yet been approved for patients with spinal cord injuries.

"The important thing for us is not just to have a scientific trial, but eventually to give more access to more people with spinal cord injuries who are used to hearing from doctors that they have to get used to the fact that they will never move again," Bloch said.

Over time, the researchers hope that the technology will advance enough that more patients will be able to access it and that it can be used in their everyday lives.

"This is our true objective," Courtine said, "to make this technology available across the world for all the patients who need it." (Weintraub, USA Today, 5/25; Whang, New York Times, 5/24; Gilbert, Washington Post, 5/24; Ghosh, BBC, 5/24)

Access this cheat sheet to learn how deep brain stimulation (DBS) devices are disrupting care delivery and generating clinical evidence.