iNDICA NEWS BUREAU-
Spinal cord stimulation restores arm, hand mobility in stroke patients
US researchers have used a device to stimulate the spinal cord to restore arm and hand mobility in two stroke patients, allowing them to perform daily life activities, like using a fork to eat a meal.
The new therapy, published on February 20, 2023, in the journal Nature Medicine, was tested on two stroke patients with moderate to severe motor impairments.
“Cerebral strokes can disrupt descending commands from motor cortical areas to the spinal cord, which can result in permanent motor deficits of the arm and hand. However, the spinal circuits that control movement remain intact and could be targeted by neuro-technologies to restore movement,” stated the abstract about this therapy published in Nature Medicine, a monthly journal that publishes original peer-reviewed research in all areas of medicine on the basis of its originality, timeliness, interdisciplinary interest and impact on improving human health.
“Here we report results from two participants in a first-in-human study using electrical stimulation of cervical spinal circuits to facilitate arm and hand motor control in chronic post-stroke hemiparesis (NCT04512690). Participants were implanted for 29 d with two linear leads in the dorsolateral epidural space targeting spinal roots C3 to T1 to increase excitation of arm and hand motoneurons. We found that continuous stimulation through selected contacts improved strength, kinematics, and functional movements, enabling participants to perform movements that they could not perform without spinal cord stimulation. Both participants retained some of these improvements even without stimulation and no serious adverse events were reported. While we cannot conclusively evaluate the safety and efficacy of two participants, our data provide promising, albeit preliminary, evidence that spinal cord stimulation could be an assistive as well as a restorative approach for upper-limb recovery after stroke,” the excerpt said.
The technology that has been developed by researchers of the US National Institutes of Health uses a set of thin metal electrodes implanted on the surface of the spinal cord. Electrical impulses from the device stimulate neural circuits in the spinal cord, priming them to receive movement signals from the brain. This engages muscles that have been weakened by a stroke, allowing patients to voluntarily lift their arms, open and close their fists, and grasp household objects.
The researchers from the US National Institutes of Health found that continuous stimulation targeting the cervical sensory nerve roots of the spinal cord immediately improved strength, range of motion, and function of the arm and hand. Stimulation also enabled participants to perform complex tasks that require more skill and dexterity, such as using utensils to eat and opening a lock, activities that they had not done in years.
Surprisingly, some benefits persisted for several weeks after the device was removed. This suggests that when combined with physical or occupational therapy, this assistive stimulation approach could lead to more robust long-term improvements in motor function.
Recent studies have used spinal cord stimulation technology to treat chronic pain and restore leg movement after spinal cord injury.
Globally, one in four people over the age of 25 suffer from a stroke, and nearly three-quarters of these individuals will have lasting deficits in the motor control of their arm and hand, causing disability and enormous impacts on daily life. There are no effective treatments for paralysis in the chronic stage of stroke, which begins six months after the initial stroke incident.
These findings provide a practical stimulation protocol for adapting an existing clinical technology to treat upper-limb paralysis following a stroke. However, more research is needed to translate the therapy into broader clinical use.