Hope for Spinal Cord Injury Victims: Paralyzed Rats Walk Again

Last month we learned that UCSD scientists restored nerve connections in lab rats with spinal cord injuries. Now researchers at the David Geffen School of Medicine at the University of California, Los Angeles, have enabled rats with spinal cord injuries to walk again. But in this new study, researchers did not reconnect nerves; rather, through a combination of drug therapy, electrical simulation, and exercise training, they enabled the rats to walk without using their brains.

The study was published this week in the journal Nature Neuroscience. Yesterday, the New York Times published an interview with head researcher Reggie Edgerton, a professor of neurobiology and physiological sciences.

Edgerton said that this study shows “that there are neuro-networks within the lumbar-sacral spinal cord capable of full weight-bearing and relatively coordinated stepping without any input from the brain. What is new here is that it demonstrates that the sensory system can actually control the stepping. This is a really important point that is unique, and most people have not thought about the sensory system as being a control system.

“The spinal cord can carry out these reflexes, these corrective movements. But in this case, what is being demonstrated is that the sensory system can also control the step, not just correct it. The information coming from the legs is going back to the spinal cord, and that spinal circuitry can interpret that sensory information. It knows how much loading is on the legs, which direction it needs to step, how fast it should be stepping. The spinal cord is smart. It can receive sensory information and make appropriate decisions without the brain.

“There is a tendency to think that stepping is occurring because of our cortical control, our conscious control,” continued Edgerton. “Most of our movements are relatively automatic. We’re not really controlling movement from the brain. The sensory system from the legs to the spinal cord, much of this control is occurring automatically. After a complete spinal injury, that sensory information is not getting to the brain, but it’s getting to the spinal circuity. That spinal circuitry knows how to interpret that information.”

So how does this therapy work? It’s based on exercising training, but drugs and electricity are used to stimulate the nervous system. Edgerton explained, “The epidural stimulation and the pharmacology is changing the functional state of that circuitry. It’s making it more excitable. Without making that spinal cord more excitable, we can’t train it. By increasing its sensitivity to the sensory information it’s getting, then we can train it.”

Edgerton hopes to begin testing the new therapy with patients within a year.

“I’m very optimistic about it,” he said, “and I’m also worried about projecting too much hope. I think there are a lot of possibilities here. I think there is a very high probability that a number of individuals with severe injuries can gain some functional improvement with this approach.

“The vision is that with the aid of a walker, individuals with complete injuries would be able to help maintain their balance and execute some effective stepping. They’re not going to be stepping normally, but small improvements can be made in an individual’s life. Just to be able to stand and take a few steps can make a big difference.”

Amazing! For years, spinal cord injury research has focused on reconnecting the spinal cord and the brain. This exciting breakthrough shows that the brain is not the only source of intelligence in the body.

Have you or a loved one suffered a spinal cord injury? If you need legal advice from an experienced Georgia spinal cord injury lawyer, call MLN Law at 404-531-9700 to schedule a free consultation.