Man moves paralysed legs using spinal cord stimulation


Mayo Clinic (Rochester, USA) researchers have used electrical stimulation on the spinal cord and intense physical therapy to help a man intentionally move his paralysed legs, stand and make step-like motions for the first time in three years.

The case, the result of collaboration with University of California Los Angeles (UCLA; Los Angeles, USA) researchers, appears today in Mayo Clinic Proceedings. Researchers say these results offer further evidence that a combination of this technology and rehabilitation may help patients with spinal cord injuries regain control over previously paralysed movements, such as step-like actions, balance control and standing.

“We are really excited, because our results went beyond our expectations,” says neurosurgeon Kendall Lee, principal investigator and director of Mayo Clinic’s Neural Engineering Laboratory. “These are initial findings, but the patient is continuing to make progress.”

The 26-year-old patient injured his spinal cord at the sixth thoracic vertebrae in the middle of his back three years earlier. He was diagnosed with a motor complete spinal cord injury, meaning he could not move or feel anything below the middle of his torso.

The study started with the patient going through 22 weeks of physical therapy. He had three training sessions a week to prepare his muscles for attempting tasks during spinal cord stimulation. He was tested for changes regularly. Some results led researchers to characterise his injury further as discomplete, suggesting dormant connections across his injury may remain.

Following physical therapy, he underwent surgery to implant an electrode in the epidural space near the spinal cord below the injured area. The electrode is connected to a computer-controlled device under the skin in the patient’s abdomen. This device, for which Mayo Clinic received permission from the US Food and Drug Administration for off-label use, sends electrical current to the spinal cord, enabling the patient to create movement.

After a three-week recovery period from surgery, the patient resumed physical therapy with stimulation settings adjusted to enable movements. In the first two weeks, he was able to intentionally:

  • Control his muscles while lying on his side, resulting in leg movements
  • Make step-like motions while lying on his side and standing with partial support
  • Stand independently using his arms on support bars for balance

“This has really set the tone for our post-surgical rehabilitation—trying to use that function the patient recovered to drive even more return of abilities,” says Kristin Zhao, co-principal investigator and director of Mayo Clinic’s Assistive and Restorative Technology Laboratory.

The Mayo researchers worked closely with the team of V Reggie Edgerton, at UCLA on this study, which replicates earlier research done at the University of Louisville, Louiseville, USA. The Mayo study marks the first time a patient has intentionally controlled previously paralysed functions within the first two weeks of stimulation.

The data suggest that people with discomplete spinal cord injuries may be candidates for epidural stimulation therapy. However, more research is needed into how a discomplete injury contributes to recovering function.