This is some big news. An amazing new surgical technique has restored brain communication with the legs of patients with paralysis from the waist down. We’ve previously reported on treatments to reverse paralysis in dogs and monkeys, but this is completely different. The four men were fitted with an array of 16 electrodes to the lumbosacral region of the spinal cord, the hub for the flow of information between the brain and the lower limbs. The testing was conducted as part of a study by the Kentucky Spinal Cord Injury Research Center at the University of Louisville.
The patients have improved dramatically since receiving the treatment. None of them can walk, but all four can move their legs and toes, some can lift their legs with weights of up to 100 kg (220 lbs) attached, and one says he is able to stand. How does these electrodes have such a dramatic effect on paralysis? New Scientist explains:
[T]he implant restores what in healthy people would be the resting potential of the spinal cord, the baseline electrical activity that keeps the cord alert, but which wanes through lack of use in people who are [paralyzed]… Once this background electrical impetus is restored artificially, the cord reawakens and can register the brain’s “intent” to move from the brain and convert this into fine movement at the motor neuron level. And by modulating the voltage for each individual and for each task, algorithms that [optimize] delivery of electrical activity for specific movement can be worked out and applied at will by the patients.
The bad news is that due to the limitations of the current device, patients can only move one side at a time. The good news is that scientists are working on refining the device, and the next implant will have 27 electrodes instead of 16. This will allow for better control and coordination. The even better news is that all four patients have regained varying degrees of bladder, bowel, and sexual function. The cure for paralysis may still be years away, but this device is improving lives today.