Bypassing spinal cord injury
A severe spinal cord injury interrupts almost all direct pathways from the motor cortex to the spinal cord, resulting in a severe paralysis and no chance of recovery. But the trauma often spare some “indirect” fibres from the midbrain and the brainstem to the spinal cord.
Now scientists from the Swiss Federal Institute of Technology at Geneva, Switzerland, led by Gregoire Courtine, investigated a special rehabilitation approach, using the spared and intact connections to functionally to reconnect the brain to the body. In the magazine Nature Neuroscience they describe their design of therapies aiming at bypassing the lesion site and restoring locomotion in an experimental SCI model. The combined interventions act over two time windows. First, a special cocktail of chemicals like monoamines and epidural electrical stimulation (named “electrochemical neuromodulation”) awakens the neural circuits. Then, the combination with a special training program enhances functionally meaningfull connections of the nerve fibres from the motor cortex with neurons in the midbrain and brainstem and, using the spared fibres, with the circuits in the spinal cord.
By repeating the gravity assisted intensive training for 9 weeks, the team was able to create a “bypass” to the injury. The spared intact connections “learned” and “took on” the tasks of the damaged ones and relayed the information from the brain to the spinal cord.
This approach could allow more patients to recover some functions and could benefit all types of injuries. Leonie Asboth, the first author of this study said “These results warrant clinical studies. While challenges lie ahead, neuro-prosthetic rehabilitation may become medical practice for improving recovery.”