When a person’s arm has become paralyzed due to a stroke, therapists often try to get it moving again using what’s known as functional electrical stimulation – this involves delivering electric shocks to the arm, causing its muscles to move. Studies have shown, however, that it works better when the patient is in charge of delivering those shocks themselves. A new device lets them do so, and it has met with promising results.
The system was developed by Intento, a company affiliated with Switzerland’s EPFL research institute. It consists of three parts: electrodes that the patient places on their arm, a controller that is operated by their “good” hand, and a tablet running custom software.
The therapist starts by selecting a desired arm movement on the tablet, and then loading it into the controller. A display on the tablet’s screen then shows the patient where the electrodes should be placed. Once those are attached, the patient sets about using the controller to deliver shocks to their arm muscles, resulting in the targeted movement – this could be something like pressing a button or picking up an object.
Ideally, once the action has been repeated enough times, the muscles will be “trained” and it will be possible for the patient to perform the movement without any external stimulation.
In a clinical trial performed at Lausanne University Hospital, 11 severely stroke-paralyzed patients – for whom other therapies hadn’t worked – used for the device for 1.5-hour daily sessions, over a course of 10 days. A claimed 70 percent of them subsequently “showed a significant improvement in their motor functions,” as opposed to just 30 percent who were undergoing conventional occupational therapy.
A larger clinical study is now being planned, after which the device will hopefully be commercialized. The research is described in a paper that was recently published in the journal Archives of Physical Medicine and Rehabilitation.