Just two patients — one with multiple sclerosis and one with paralysis from a stroke — participated in these studies on the feasibility of using implanted electrodes to restore the ability to walk.
Although it’s exciting so see assistive technology helping individuals, isolated short-term successes in a lab don’t equate to an effective treatment for broad populations of patients, but this news release from Case Western Reserve University doesn’t deliver that caution strongly enough. Nor does it discuss costs, offer comparisons with other treatment options, or explain potential risks with this technology, which was developed with the Louis Stokes Cleveland Veterans Affairs Medical Center. The news release nicely describes how this technology affected these two patients, including videos showing them walking with and without the electronic stimulation.
Stroke and multiple sclerosis are two common causes of impaired walking. Case studies like these are exciting and may support further research into the use of implanted devices to restore specific muscle contractions necessary for walking, which may in turn lead to greater mobility and improved cardiovascular health and quality of life.
There’s no discussion of costs. While it may not be possible to put an exact price tag on a treatment that is so preliminary, we think some estimate of the costs involved is warranted. One study put the indirect costs of multiple sclerosis at more than $30,000 per person per year, due mainly to impaired mobility. The news release hints at the high cost by mentioning that the researchers are seeking funding to fit one of the patients with a permanent device in a clinical trial.
The news release describes both men’s improvement in terms of distance walked with the aid of electronic nerve stimulation. For example, the stroke patient’s ability to move “without the system was about 19 yards per minute; with the system, 47 yards per minute,” the news release states, while training improved his speed with the system turned off to “23 yards per minute, indicating therapeutic benefit.” His distance improved from 83 yards to 1,550 yards, almost a mile.
It states that the multiple sclerosis patient “went from the two steps to consistently walking more than 30 yards during the (90-day) trial. In that time, he used a walker to help maintain his balance.”
The news release also provides quotes from the men and links to videos that show the men’s abilities to walk with and without electronic stimulation.
There’s no mention of potential harms, such as the risk of infection from implanted electrodes.
In research that is this preliminary, there should be ample discussion of the limitations. That’s missing here.
The news release doesn’t effectively convey that a large-scale clinical study is needed to determine whether this technology can be effective for large groups of patients, particularly outside the clinical setting. Patients with these conditions have a wide range of degrees and types of impairment, and it’s unclear who could benefit or whether the technology might have to be adapted for different patients.
Also, there’s not much detail on how much effort was required for these patients to achieve and maintain mobility improvement. According to one of the case studies, the stroke patient came to the lab for 46 sessions of gait training over 30 weeks, spending two to three hours each time. The necessity of intense training to use this technology might limit its applicability.
The news release gives some sense of what’s involved with operating this system, describing how patients push a button on a controller to trigger electrical pulses that stimulate the nerves. It also quotes one patient as stating that “distance is a challenge.”
The release doesn’t engage in disease mongering. It does provide some perspective, stating that a “substantial” number of people could stand to benefit from this technology. It further states:
“The National Multiple Sclerosis Society estimates that more than 2.3 million people have the disease worldwide. Surveys have found that 93 percent suffer gait impairment within 10 years of diagnosis and 13 percent report they are unable to walk twice a week. Other research has found that 6 million to 7 million people live with stroke nationally and nearly 30 percent require assistance to walk.”
The release doesn’t note the funders but they are listed on the sidebar of EurekAlert!, a host site for the news release.
There’s scant reference to existing treatments, with just one quote that briefly mentions physical therapy:
In each patient, “the pulses are sent in a pattern that is close to how normal muscles work,” said Rudi Kobetic, a principal investigator at the Stokes Cleveland VA and APT Center. “We try to time the pattern to stimulation so that it’s integrated with their ability. Similar to regular physical therapy, we can see results.”
We would have liked to see discussion of what hurdles this technology must overcome to be made available to the general patient population, as well as what types of patients might stand to benefit.
While functional electronic stimulation has been used for many decades to aid patients with spinal cord injuries, stroke, multiple sclerosis and cerebral palsy, among other conditions, this release suggests in the fourth paragraph that this is the first time an implantable FES device has been used in a patient with multiple sclerosis.
We think the release should have been more transparent about the fact that research into this implantable technology has been going on for many years. For example, a 2005 study reported in the journal Spinal Cord describes how researchers implanted FES systems in nine pediatric patients with spinal cord injuries.
The release does offer some context, stating that researchers “hope these studies will lay the foundation for implanted systems that restore some independence to people with MS or who have suffered a stroke.” Further, it quotes a researcher saying that this technology has been used primarily for therapy in stroke patients and this application constitutes “a more long-term assistive system” for those patients.
The release doesn’t rely on sensational language. However, the headline could easily mislead casual readers into thinking that nerve stimulation could help all MS and stroke patients improve their ability to walk, when in fact this specific technology was tested on just two patients.