Washington, Apr 4: US scientists have helped a man intentionally move his paralysed legs, stand and make steplike motions for the first time in three years, by using electrical stimulation on his spinal cord and intense physical therapy.
It marks the first time a patient intentionally controlled previously paralysed functions within the first two weeks of stimulation, researchers said.
The results offer evidence that a combination of this technology and rehabilitation may help patients with spinal cord injuries regain control over previously paralysed movements, such as steplike actions, balance control and standing.
"We're really excited, because our results went beyond our expectations," said Kendall Lee, director of Mayo Clinic's Neural Engineering Laboratory in the US.
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 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 intentionally was able to control his muscles while lying on his side, resulting in leg movements.
He was also able to make steplike motions while lying on his side and standing with partial support as well as stand independently using his arms on support bars for balance.
Intentional, or volitional, movement means the patient's brain is sending a signal to motor neurons in his spinal cord to move his legs purposefully.
"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," said Kristin Zhao, director of Mayo Clinic's Assistive and Restorative Technology Laboratory.