Several paraplegic patients have returned to walking after scientists tested a treatment that combined stimulation of the spinal cord with physical therapy, offering new hope for disabled people.
Jered Chinnock , 29, of Wisconsin, was unable to move or feel anything mid-torso down after damaging his spinal cord in a snowmobile accident while riding with friends in 2013.
But, thanks to this experimental therapy, Chinnock is able to stand up and walk with the help of a walking stick and the support of his physical therapist.
“What it’s teaching us is that those networks of neurons underneath a spinal cord injury can still function after paralysis,” says Kendall Lee, a neurosurgeon and director of the Neural Engineering Laboratories at the Mayo Clinic.
“After the electrical stimulation, the patient was able to gain voluntary control. The reason this is important is because the patient’s mind and thoughts were able to drive movement in his legs . And we got him to stay independent and to keep going. their own steps, “clarifies Lee.
In similar trials at the Kentucky Spinal Cord Injury Research Center at the University of Louisville, two patients with complete spinal cord injury were also able to walk again, while two others were able to stand independently.
The patients had electrodes implanted in the spine below the injury site to stimulate latent neural networks that control movement of the hips, knees, ankles, and toes.
Physical therapy ultimately aims to retrain the spinal cord to “remember” the walking pattern by repeatedly practicing position and gait while stimulating neural areas. Over time, the brain begins to associate muscle movement with these thoughts.
The therapy is so novel that even scientists at the Mayo Clinic and the University of California don’t fully understand why it works or how the brain can communicate the intention to move to the nerves.
“ It is likely that the spinal cord that has been stimulated is somewhat asleep and has been able to control that neural activity, being able to take back the information from the brain to allow voluntary control of the legs. What is significant is that it is possible to regain control intentional, “Lee continues.
In the study, which began in 2016, Jered Chinnock participated in a 22-week physical therapy experiment and then had an electrode surgically implanted by Dr. Lee.
In the first week, the patient wore a harness to reduce the risk of falls and to provide upper body balance.
By week 25 after the operation, he no longer needed the harness. And, towards the end of the study period, Chinnock learned to use his entire body to transfer weight, maintain balance, and propel himself forward.
After 113 rehabilitation sessions, Chinnock is able to walk with assistance for 16 minutes and, in total, has taken 331 steps, covering more than 100 meters, along a football field.
“I think the real challenge begins now, and it’s about understanding how this has happened, why it happened, and which patients will respond to therapy,” concluded Kristin Zhao, director of the Mayo Clinic Restorative and Assistive Technology Laboratory.
Reference: Megan L. Gill, Peter J. Grahn, Jonathan S. Calvert, Margaux B. Linde, Igor A. Lavrov, Jeffrey A. Strommen, Lisa A. Beck, Dimitry G. Sayenko, Meegan G. Van Straaten, Dina I Drubach, Daniel D. Veith, Andrew R. Thoreson, Cesar Lopez, Yury P. Gerasimenko, V. Reggie Edgerton, Kendall H. Lee, Kristin D. Zhao. ‘Neuromodulation of lumbosacral spinal networks enables independent stepping after complete paraplegia’. Nature Medicine DOI 10.1038 / s41591-018-0175-7
CA Angeli et al . Recovery of over-ground walking after chronic motor complete spinal cord injury. New England Journal of Medicine . Published online September 24, 2018. doi: 10.1056 / NEJMoa1803588.
Image credit: Mayo Clinic
