A happy, and amazing, study to start the day with. Using implanted electrodes, researchers are helping paraplegics move their legs again.
Patients who have severe spinal cord injuries can often become paralyzed. Depending on the type of injury and the area of the cord injured, the patient may have both lower limbs paralyzed, or may have all four limbs paralyzed, among other possible outcomes.
Having the lower limbs paralyzed is referred to as paraplegia. A new technique was used successfully on four young male paraplegics to help restore motor function to their lower limbs. All four of these men had sustained injuries to their spinal cords that caused them to lose motor control of their legs. In essence, they couldn’t move any muscles in their legs or feet, much less walk or stand.
Currently, patients who are paraplegic would always need assistive devices to move. For example, they might need to use a wheelchair or some other device. The patients selected had all been paraplegics for some time and had been receiving physical therapy to their leg muscles to prevent wasting and malformation.
In a normally functioning spinal cord, sensory messages travel from the feet and legs to the brain. When the patient needs to move his lower limbs, the brain sends impulses through motor nerves to the muscles causing them to move. The nerve cells that perform these functions travel from one place to another via the spinal cord. Think of the spinal cord as an ethernet cable connecting the computer to the router. It transmits information from the brain (computer) to the router (muscles) and vice versa (as the router receives external input to transmit to the computer.)
These men all had injuries that damaged their “ethernet cables.” To fix that, using the computer analogy, you “just” replace the cable. But the spinal cord is much more complex and can’t be replaced as easily as a cable. Attempts to somehow fix the damaged area of the spinal cord (e.g., by using stem cells) have had somewhat limited results.
This technique acts to bypass the injured area completely.
Neurosurgeons implanted electrodes below the level of the injury to the cord. These electrodes emit current in specific patterns in response to either sensory input from the patient or other signals. These generated electrical patterns, stimulate motor nerves that run to the muscles. When stimulated, they cause the muscles to react. In these cases, the men can use sound cues. The patients use a hand-held device that can activate the spinal electrode array, turning it on of off. Then, using voice commands that are picked up by sensors and translated into electrical impulses, they can order their legs, feet and toes to move. The video below shows one of the patients telling his leg to move and it responds almost instantly.
The movements are clumsy, but considering that prior to this the patients had no ability to move these limbs at all, the results are amazing. Also the video shows how another patient, former Oregon State pitcher Rob Summers, who was paralyzed in a hit-and-run accident, can now get himself into a sitting position, from laying back, using his legs. You’ll see Summers laying back, then lifting his legs to help him sit back up. This is something that he could only do in the past by using his arms to pull himself upright (or by having someone assist him), since he could lift his legs.
It still remains to be seen how these patients will progress in the future. They’ll continue to have physical and occupational therapy. Perhaps they’ll be eventually be able to walk with limited or no assistance.
The researchers who did the study are actively continuing to work. They are going to do implants in additional patients to gather more data. They are also working to improve the hand-held stimulator as their patients continue with ongoing therapy.
This is a follow-up study done at the University of Louisville by Dr. C. Angeli, et al. Part of the funding for this research came from the National Institutes of Health. Continued funding of this, and many other projects, is contingent on the government providing research funds. With the current state of affairs in Washington, funding for research always seems near the top of the list to feel the budget-cutting axe. I did a story on the horrific research cuts that occurred thanks to the sequester. I fear that funding for medical research – for diabetes, heart disease, Alzheimer disease, mental health, HIV, stroke, cancer research and hundreds of other ailments, will continue to decrease.