Scientists hail pivotal step in treatment of paralysis
Hope for patients with spinal cord injuries as new technique helps them to walk again unaided
PARALYSED patients are walking again after scientists coaxed undamaged nerves into taking over leg movements in a world’s first that offers new hope for disabled people.
Jered Chinnock, 29, of Wisconsin, was left unable to move or feel anything below the middle of his torso after damaging his spinal cord when he was flung from his snowmobile while riding with friends in 2013.
But in a groundbreaking technique that combines electronic spinal cord stimulation and physical therapy, Mr Chinnock is now standing up and taking steps with just the assistance of a walking frame and gentle support from his physiotherapist.
“What this is teaching us is that those networks of neurons below a spinal cord injury still can function after paralysis,” said Dr Kendall Lee, neurosurgeon and director of Mayo Clinic’s Neural Engineering Laboratories. “The reason this is important is because the patient’s own mind and thoughts were able to drive the movement in his legs.”
In the study, which began in 2016, Mr Chinnock participated in 22 weeks of physical therapy and then had an electrode surgically implanted by Dr Lee. In the first week after surgery, he was attached to a harness to lower his risk of falling and to provide upper body balance.
By week 25 after the operation he no longer needed a harness, and by the end of the study period, after 43 weeks, Mr Chinnock had learnt how to use his entire body to transfer weight, maintain balance and propel forward, requiring just a few verbal cues and glances at his legs.
The therapy is so new that even scientists at the Mayo Clinic and University of California do not fully understand why it works .
“Now I think the real challenge starts, and that’s understanding how this happened, why it happened, and which patients will respond,” said Dr Kristin Zhao, director of Mayo Clinic’s Assistive and Restorative Technology Laboratory. “It was only after the stimulator was placed that he was able to move. Just with rehab there was no recovery.”
In similar trials at the Kentucky Spinal Cord Injury Research Center, University of Louisville, two patients with complete spinal cord injury were also able to walk again, using just a frame, while a further two could stand independently.
They had electrodes implanted on their spine below the injury to stimulate dormant neural networks that control movement of the hips, knees, ankles and toes.
Physiotherapy then aims to retrain the spinal cord to “remember” the pattern of walking by repetitively practicing standing and stepping while the neural areas are being stimulated. Over time the brain begins to associate the muscle movement with thoughts. In Britain every year around 1,200 people are paralysed from a spinal cord injury and there are approximately 40,000 people living with paralysis in the UK. But the new research shows that undamaged nerves can be repurposed to bring back motor function
Kelly Thomas, 24, of Florida, who was injured in a car accident, was one of the first to receive the new therapy at the University of Louisville.
“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 accident,” she said. “The first day I took steps on my own was an emotional milestone in my recovery that I’ll never forget, as one minute I was walking with the trainer’s assistance and, while they stopped, I continued walking on my own.
“It’s amazing what the human body can accomplish with help from research and technology.”
Jeff Marquis, a 35-year-old from Wisconsin, who now lives in Louisville, said: “The first steps after my mountain biking accident were such a surprise and I am thrilled to have progressed by continuing to take more steps each day. In addition, my endurance has improved, as I’ve regained strength and the independence to do things I used to take for granted like cooking and cleaning.”
The results were published in Nature Medicine and The New England Journal of Medicine.