A new breakthrough is giving hope to millions of people suffering from debilitating spinal injuries. A revolutionary implant helped a small group of paraplegic patients take steps by stimulating their spinal cords electronically. By coupling intense training with the small implant, two of the group of four were able to walk unassisted for the first time since their paralysis.
The study, which was published in the New England Journal of Medicine, follows the development of the “epidural stimulation” process put into place by teams from the Frazier Rehabilitation Institute and the University of Louisville Kentucky Spinal Cord Injury Research Center. How does it work? When a severe spinal injury occurs, signals from the brain that trigger movement are lost at the site of the injury. In this case, researchers worked on the assumption that small signals were still crossing over the place of injury, they just weren't enough to make motion occur.
By placing a set of 16 electrodes in the lower back of the patients, below the site of injury and implanting a battery in the abdomen, they hoped to send strong enough signals to trigger movement. The battery, which controls the intensity, duration, and frequency of the stimulation, is controlled wirelessly. Once the implant is turned on, the idea is that the stimulation would cause a reaction from the spinal cord, making it more receptive.
“It is like it is more aware, it actually can listen to that little whisper from the brain that is still there and it can generate the motor pattern,” Dr. Claudia Angeli of Kentucky Spinal Cord Injury Research Center at the University of Louisville told The Guardian.
Patients underwent an extensive amount of training to connect the stimulation with movement—a critical concept to ensure success. Both Kelly Thomas and Jeff Marquis, who had incurred spinal injuries in a car and bike accident respectively, were able to walk unassisted. Prior to the study, each had undergone traditional rehabilitative therapy and had retained a slight sensation in their lower bodies after their accidents.
Two other participants, who had no sensation below their injury sites, were not able to walk independently but made strides in recovery. Both became able to sit and stand unassisted, while one was also able to make some steps on a treadmill while supported. One of the patients had a spontaneous hip fracture during the study and wasn't able to train for a year.
The patients dedicated themselves fully to the process, meeting with researchers two hours a day, five times a week in order to practice connecting the mental connection with the physical movement. Thomas was able to walk with a walker and stand unassisted for 50 minutes after 81 sessions over 15 weeks. Marquis, whose injury is more severe, was able to walk independently using poles after 278 sessions over 85 weeks.
“Being a participant in this study truly changed my life, as it has provided me with a hope that I didn’t think was possible after my car accident,” shared Thomas. This incredible achievement is the first step in helping even more people with paralysis gain back their motor skills. At the moment, movement is only possible when the implant is turned on. However, there is hope.
An earlier study by one of the researchers involved in the project showed that a patient was able to regain movement without stimulation after 3.5 years of training. With improved stimulation technology and more research, researchers remain hopeful that there is endless potential for the process.
Watch as these spinal cord injury patients take their first steps.
h/t: [IFL Science]