A groundbreaking achievement by Mayo Clinic and UCLA researchers allowed a man, who had lost motor functions after a spinal cord injury, to move his legs for the first time in three years.
The collaborative project involved the use of an epidural stimulator, which is essentially an electrode, implanted near the injured area to deliver electrical stimulation to the spinal cord.
This research is based on a previous study by scientists at University of Louisville, Kentucky, who first experimented with stimulator implants on four paraplegic patients.
Mayo Clinic adapted and advanced the procedure, announcing in a news release that this technology, combined with intense physical therapy, has successfully resulted in volitional movements and enabled the patient to perform steplike motions, control his balance and eventually stand up.
The new study, which lead author Dr. Kendall Lee described as a "major breakthrough," was published in the journal Mayo Clinic Proceedings.
"We've actually gone beyond our initial hopes," said Dr. Lee, who is a neurosurgeon and the director of Mayo's Neural Engineering Laboratory.
Epidural Stimulation In Spinal Cord Injuries
The patient involved in the Mayo Clinic study, 26-year-old Jered Chinnock, has been diagnosed with a motor complete spinal cord injury following a snowmobile accident, which left him paralyzed and unable to feel anything below the middle of the torso.
After undergoing 22 weeks of rehabilitation therapy in preparation for the study — during which he trained three times a week to strengthen his muscles and was continuously monitored for any sign of change — researchers reached the conclusion his injury was discomplete, rather than complete.
With this type of injury, some neural connection within the spinal cord still remains, albeit dormant, as explained by Prof. Reggie Edgerton from UCLA.
"We don't have to rebuild them necessarily, just reactivate them to a point," he said in a statement.
His past research led him to discover the spinal cords of animals still retained electrical impulses for routine movements without them being signaled by the brain.
In his own study, Prof. Edgerton used electrical stimulation to make lab rats with broken spinal cords walk again.
Volitional Control Of Paralyzed Muscles
Once his physical therapy was completed, Chinnock underwent implant surgery to have an electrode placed in the epidural space close to the spinal cord. The electrode was linked to a device implanted in the skin above the abdomen and controlled via computer.
Although the device is not currently approved, the U.S. Food and Drug Administration authorized Mayo Clinic to use it for the study in order to perform electrical stimulation of the spinal cord.
Three weeks after the implant surgery, Chinnock resumed physical therapy with stimulation settings adjusted to enable movements. Within 14 days he was able to control his previously paralyzed muscles while lying on his side, make steplike motions and stand independently — a premiere in electrical stimulation studies.
Mayo Clinic plans to undertake further studies to determine if the progress obtained with the spinal cord stimulator can lead to the recovery of other motor functions.