For decades scientists have been trying to find a treatment, which would help people with spinal cord injuries walk.
Researchers have known that stimulation and training can improve muscle control somewhat after such injuries in animals, writes The New York Times.
Last year media were swarming with the information about of a 23-year-old paraplegic who regained the ability to stand for a few minutes at a time after a similar program.
Swiss research team performed the study which is the most comprehensive and rigorous presentation to date of what is possible. So, experts are already working on technology to test the techniques in humans.
Now there’s a striking new demonstration of how one approach might work: Spinal nerve stimulation helped rats in a Swiss lab overcome paralysis to walk and climb stairs.
That may sound unbelievable, but similar progress has been made in people, too. The difference is that this time the particular technique is used.
“It’s a natural extension of exciting work that’s been done by many groups,” explained Dr. John McDonald, director of the International Center for Spinal Cord Injury at Kennedy Krieger Institute in Baltimore.
The report, published online on Thursday in the journal Science, proves that nothing is impossible. The rats have undergone complete rehabilitation after a disabling blow to the spinal cord. After weeks of training, many of the rodents could walk as well as before the injury, and some could run.
However, the treatment canâ€™t be applied to all spinal injuries. The animalsâ€™ spinal columns were cut without being completely severed; there remained some nerve connections that extended intact through the injured area.
But this is also the case for a substantial proportion â€” perhaps a quarter to a third â€” of people whose injuries are severe enough to confine them to a wheelchair.
â€śThis is a very exciting study, and my first thought is that it is a proof of principle for treating spinal cord injuries from a wide variety of conditions, including cancer and even multiple sclerosis,â€ť said Dr. Vineeta Singh, a neurologist at San Francisco General Hospital and the University of California, San Francisco.
â€śThereâ€™s a huge potential to refine this model to mimic more humanlike conditions,â€ť added Dr. Vineeta who wasnâ€™t involved in the study.
To conduct the study, the researchers gave a group of 10 rats the same surgical injury, cutting all direct nerve connections to the hind legs but stopping short of severing the spinal cord. The rats lost the use of their hind legs, but not their front legs.
The scientists provided stimulation of two types in three places: electrically, in the motor area of the brain and in the spinal cord below the injury, and chemically, infusing the wound area with drugs thought to promote growth.
After two to three weeks of 30-minute sessions, the rats began to take their first steps. After two months, all of the rodents could walk on their own, and some could run and climb stairs.
â€śThe way I think about it is that there is this little island of spare tissue in the injured area, and the neurons in that island begin to act as a relay center, bypassing the injury,â€ť Dr. Courtine, who is also affiliated with the University of Zurich, said in a telephone interview.