The implant that helps paraplegics walk
In a breakthrough that offers hope to paraplegics, three people paralyzed from the waist down have regained the ability to walk after having electrodes implanted in their spinal cords. Paralysis often occurs after a spinal injury because signals sent from the brain can no longer reach the nerves that activate muscles, or because those signals are too weak to stimulate movement. But scientists believe that the spinal cord can act as an amplifier and boost those signals when electrically stimulated. To test this theory, researchers implanted tiny electrodes between patients’ vertebrae, below the level of the injury, and delivered a weak electrical current directly into the spinal cord. The results from two separate U.S. studies have been spectacular, reports the Associated Press. One patient, Jered Chinnock, could move his leg muscles within two weeks; after months of intensive physical therapy, he could walk the length of a football field with assistance. “It feels like science fiction,” said Chinnock, 29. “The first day they turned it on, it was almost mindblowing.” The treatment doesn’t repair the damage—the patients cannot move their legs when the electrodes are off—and two other paraplegics weren’t able to take independent steps. “Now I think the real challenge starts,” says Kristin Zhao, from the Mayo Clinic, “and that’s understanding how this happened, why it happened, and which patients will respond.”