A new treatment that combines physical therapy and a non-invasive method of stimulating nerve cells may offer some people with spinal cord injuries the use of their hands and arms.
Almost 18,000 Americans suffer traumatic spinal cord injuries every year. Many of these people are unable to use their hands and arms and cannot do daily tasks, such as eating, cleaning or drinking water without help.
The new treatment helped six Seattle area participants to regain some hand and arm mobility. This increased mobility lasted at least three to six months after the end of treatment. The findings appear in the newspaper IEEE Transactions in Neural Systems and Rehabilitation Engineering.
“We use our hands for everything - eating, brushing your teeth, buttoning a shirt. Patients with spinal cord injury recover hand function as the first absolute priority for treatment. It is five to six times more important than anything else that asks for help, ”says lead author Fatma Inanici, a senior postdoctoral researcher in electrical and computer engineering at the University of Washington who completed this research as a doctoral student in medicine. rehabilitation at the Faculty of Medicine.
“At the beginning of our study,” says Inanici, “I did not expect an immediate response from the first stimulation session. As a rehab doctor, my experience was that there was always a limit to how much people would recover. But now it seems that this is changing. It is very gratifying to see these results. "
'A dramatic change'
After a spinal cord injury, many patients undergo physical therapy to help them try to regain mobility. Recently, a series of studies has shown that implanting a stimulator to supply electrical current to a damaged spinal cord can help paralyzed patients to walk again.
For the current study, the researchers combined stimulation with standard physical therapy exercises, but stimulation does not require surgery. Instead, it involves small patches that stick to a participant's skin like a band-aid. These patches are placed around the injured area on the back of the neck, where they release electrical pulses.
The researchers recruited six people with chronic diseases spinal cord injuries. All participants had been injured for at least a year and a half. Some participants were unable to move their fingers or thumbs, while others had some mobility at the beginning of the study.
To explore the feasibility of using the skin surface stimulation method, the researchers designed a five-month training program. During the first month, the researchers monitored the baseline movements of the participants' limbs each week. Then, for the second month, the team put the participants in intensive physical therapy training, three times a week, for two hours straight. For the third month, participants continued physiotherapy training, but with added stimulation.
"We turned on the device, but they continued to do exactly the same exercises as the previous month, progressing to slightly more difficult versions if they improved," says Inanici.
In the last two months of the study, the researchers divided participants into two categories: Participants with less serious injuries received another month of training alone and then a month of training plus stimulation. Patients with more severe injuries received the opposite - training and stimulation first, followed by only training second.
While some participants recovered some hand function during training alone, all six saw improvements when stimulation was combined with training.
“Both people who had no hand movement at the start of the study started moving their hands again during stimulation and were able to produce a measurable force between the fingers and the thumb,” says senior author Chet Moritz, associate professor of engineering electrical and computing, rehabilitation medicine and physiology and biophysics. "This is a dramatic change, from going completely paralyzed below the wrists to moving your hands at will."
Improvements beyond hands and arms
Some participants also noticed other improvements, including a more normal heart rate and better regulation of body temperature and bladder function.
The team followed the participants for up to six months after the training and found that these improvements remained, despite there being no further stimuli.
“We think that these stimulators bring the nerves that make your muscles contract very close to being active. In fact, they don't make the muscle move, but they make it ready to move. You are prepared, like the sprinter at the beginning of a race, ”says Moritz, who is also co-director of the Center for Neurotechnology.
"So, when someone with a spinal cord injury wants to move, the few connections that may have been spared around the injury are enough to cause the muscles to contract."
Research is advancing to help people at the clinic. The results of this study have already informed the design of an international clinical trial in several locations that Moritz will co-lead.
“We are seeing a common theme at all universities - stimulating the spinal cord electrically it's making people better, ”says Moritz. “But it takes motivation. The stimulator helps you do the exercises, and the exercises help you to get stronger, but the improvements are gradual. Over time, however, they add up to something that is really surprising. "
The Center for Neurotechnology, the Washington State Spinal Cord Injury Consortium and the Christopher and Dana Reeve Foundation funded the work.
Source: Washington University