Personalized epidural electrical stimulation (EES) restored independent motor movements in three patients with complete sensorimotor paralysis hours after therapy began, data from the ongoing showed.
Within a single day, spinal cord stimulation programs enabled these patients to stand, walk, cycle, swim, and control their trunk movements, reported Jocelyne Bloch, MD, of Lausanne University Hospital in Switzerland, and Grégoire Courtine, PhD, of the Swiss Federal Institute of Technology in Lausanne, and co-authors in
The study used technology specifically developed to restore motor function, zeroing in on the dorsal roots involved in leg and lower trunk movements, Bloch and Courtine said in a press briefing.
"Our breakthrough here is the longer, wider implanted leads with electrodes arranged in a way that corresponds exactly to the spinal nerve roots," Bloch said. "That gives us precise control over the neurons regulating specific muscles."
The new, soft implanted leads are surgically placed directly on the spinal cord, underneath the vertebrae. The technology relies on specialized software that "allows us to model the spinal cord so it's very easy for physical therapists and patients to configure an activity-dependent stimulation program," Courtine said. By clicking a simple device or a tablet, users can choose what activity they want to perform.
Participants in the first-in-man study included three people, 29 to 41 years old, who had traumatic thoracic spinal cord injury years earlier and complete sensorimotor paralysis. After leads were implanted, all patients could step on a treadmill, though gait patterns were awkward at first.
Within days, all three study participants could take as many as 300 steps independently with body support. One participant, Michel Roccati, told reporters he could walk with body support 11 days after the procedure, and that he could feel his body touching the ground and his muscles contracting when he walked.
Because of the way the technology is designed, patients can perform their training exercises at home or outdoors. "I've been through some pretty intense training in the past few months, and I've set myself a series of goals," Roccati said. "I can now go up and down stairs, and I hope to be able to walk one kilometer by this spring."
Historically, EES has been delivered using repurposed technologies that were designed to alleviate pain, Courtine pointed out. These technologies used electrodes that targeted the dorsal column, but recovering motor functions requires targeting the dorsal roots, he said.
Whether the technology will work in other patients, including older people, is not yet known. The researchers are working with Onward Medical, a medical technology company, to further study and develop the approach.
Disclosures
The study was supported by Wings for Life, the Defitech Foundation, the International Foundation for Research in Paraplegia, Rolex for Enterprise, Carigest Promex, Riders4Riders, ALARME, the Panacée Foundation, the Pictet Group Charitable Foundation, the Firmenich Foundation, Onward Medical, European Union Horizon 2020, Swiss National Science Foundation, European Research Council, the Commission of Technology and Innovation Innosuisse, and the EPFL fellows program.
Researchers reported relationships with Onward Medical, a company with direct relationships with the presented work, and ZMT Zurich MedTech AG, which produces Sim4Life software.
Primary Source
Nature Medicine
Rowald A, et al "Activity-dependent spinal cord neuromodulation rapidly restores trunk and leg motor functions after complete paralysis" Nat Med 2022; DOI: 10.1038/s41591-021-01663-5.