Stimulation improves hand function after spinal cord injury

A non-invasive spinal cord stimulator safely improves upper extremity function in patients with cervical spine disease. Spinal cord injury (SCI), results of a prospective non-significant risk trial suggest.

In this study, this device (ARC-EX, ONWARD Medical) improved at least one measure of hand and arm muscle strength and at least one measure of hand and arm function in 72% of people with chronic neck injuries. It was shown that

Additionally, 90% of study participants improved their upper extremity strength or function.

The intervention also improved sensory scores, improved quality of life and sleep, decreased frequency and severity of muscle spasms, and reduced pain.

“This treatment has real implications for improving real-life function and quality of life for people with quadriplegia,” said study author Crawford Institute Shepherd Center and Emory University Rehabilitation Medicine. said Dr. Edel C. Field-Fort of the Department. Atlanta School of Medicine said in a press conference.

“Simple things like using an ATM card, putting a key in a lock, or opening a candy wrapper are things we take for granted, but even small improvements in these functions can improve our ability to be independent and improve our quality of life. can make a huge difference,” Fieldfort continued.

It was discovered that Published online on may 20th natural medicine.

About 18,000 people experience a spinal cord injury each year in the U.S. Of those, about 60 percent suffer from quadriplegia (also called tetraplegia), a condition in which the person has no or very limited function of the hands, arms and legs, Field-Forte said.

The single-arm, open-label trial (Up-LIFT) enrolled 64 adult men aged 22 to 75 years (mean age approximately 47 years) at 14 sites in the United States, Canada, the United Kingdom, and the Netherlands. Participants had traumatic non-progressive cervical (C2-C8) SCI more than 12 months before enrollment, but in some cases the injury occurred more than 30 years before the study.

Study participants must have an American Spinal Injury Association Disability Scale classification of B, C, or D, a Graded Redefinition Assessment of Strength, Sensitivity, and Grasp Strength (GRASSP) Grasp Strength (Reach and Grasp) score of 10 or higher, or Must have a GRASSP strength score ≥. 30.

You must also have a referral from your doctor or therapist for upper extremity training.

Participants who were on a prescription and still required antispasmodic medication had to reduce their total dose to less than 30 mg/day before enrollment and remained on stable medications throughout the study.

intensive rehabilitation

Study participants underwent an intensive two-month rehabilitation program and then continued the program for an additional two months with stimulation added during each rehabilitation session. Participants completed a minimum of 12 and a maximum of 20 in-hospital rehabilitation sessions per month.

This study design allows participants to serve as their own controls, which is the most appropriate way to control for possible impairments, reactivity, and large variations in optimal stimulation doses between participants. The authors said that there is.

The stimulator includes two surface electrodes placed above and below the lesion (usually one rostral and one caudal vertebral segment). Two large return electrodes are placed over the iliac crest or clavicle.

The device delivers a “very high-frequency waveform” — 10 kilohertz (kHz), or 10,000 times per second — causing the brain to vibrate with each stimulation pulse, Dr. Chet Moritz, professor of electrical and computer engineering and rehabilitation medicine at the University of Washington in Seattle and lead author of the study, said at a briefing.

“This is thought to effectively numb or anesthetize the skin beneath the electrodes. This allows access to the sensory nerves that energize the spinal cord, leading to enhanced function, nerve recovery and “This could lead to improved plasticity,” Moritz said.

Moritz added that while some functional recovery was expected during the rehabilitation-only period, most of that improvement plateaued during the two-month rehabilitation period.

The primary efficacy endpoint tested the hypothesis that more than 50% of participants would experience significant improvements in both muscle strength and function from the end of the rehabilitation-only period to the end of the stimulation period.

Participants are considered responders if they meet the minimum important difference (MID), calculated as the change in score between the start and end of the stimulation period, for at least one of the intensity measurements—for spinal cord injury. International Standards for Neurological Classification – Upper Limb Measurement Scale (ISNCSCI-UEMS) score (MID = 2 point improvement), GRASSP muscle strength score (MID = 4 point improvement), or grip or pinch strength (MID = ≥ 6-N improvement) — and at least one of the functional measures consisting of Upper Extremity Efficiency Test (CUE-T) score (MID = 4 point improvement) and GRASSP Grasp Performance Score (MID = 2 point improvement).

Of the 60 participants who completed the study, 43 (71.7%) met or exceeded MID criteria for at least one outcome in the strength domain and at least one outcome in the functional performance domain.

There was a significant improvement in pinch force with stimulation compared to rehabilitation alone (mean difference 4.8; mean difference 4.8). P = .002), GRASSP comprehension score (mean difference, 1.6; P < .001), GRASSP intensity score (mean difference 2.8; P < .001), ISNCSCI-UEMS score (mean difference, 2.2; P < .001).

Approximately 90% of participants met MID criteria for at least one strength or Functional results.

increased sensation

In addition to improvements in muscle strength and function, ISNCSCI total sensory scores also increased significantly (mean difference 9.6, mean difference 9.6). P < .001) response to stimulation therapy compared to rehabilitation alone.

Participants who were able to use their hands to some degree “almost universally had improvements in strength, function, and sensation,” Fieldfort said. “About half of the participants who didn't move at all also showed improvement in the numbers we measured.”

Fieldforte added that he is keen to investigate what indicators patients are likely to respond to. “This helps us identify what it takes to turn people who don’t meet the responder category into responders.”

In this study, self-reported EuroQol 5-dimension 5-point scale scores (mean difference 1.7; mean difference 1.7; Po < .028), response to stimulation compared to rehabilitation alone.

Additionally, the frequency of muscle twitching after stimulation was significantly reduced (P = .009), improved sleep quality (P = .025), and pain relief (P = .04).

A total of 238 adverse events occurred across studies. constipation Urinary tract infections have also been reported. Forty-four adverse events were device-related, but none were serious. The incidence and nature of adverse events are consistent with published reports on people with chronic cervical spinal cord injuries, the authors said.

The researchers considered it inappropriate to expose patients with quadriplegia, for whom no treatment is available, to the potential risk and discomfort of sham stimulation without the desired effect, so the device's standard The researchers said they decided not to conduct a full randomized controlled trial. .

In preliminary studies, the research team identified physiological changes that “could never be attributed to a placebo effect,” Moritz said. These include sweating, slowed heart rate, and blood pressure that returns to normal within a few days after stimulation.

working hands

Two study participants appeared at the press conference and detailed how the intervention changed their lives. One of the participants, a woman who experienced SCI after falling from a horse 14 years ago, said she had experienced “very positive results” with the intervention, including “improved grip strength and a much stronger left hand. “Now I can use it to let go.” Fasten your seatbelt or put her hair in a ponytail.

“Everyone with a spinal cord injury wants to be able to walk again, but in the case of quadriplegia or quadriplegia, the most important thing is to be able to move your hands,” she says.

Another participant who was injured in a wrestling accident in 2014 said the stimulation improved his typing speed by about 30% and he can now help in the kitchen and tie balloons for children's birthday parties. .

Moritz said the stimulation amplitude could be individualized to such people and adjusted for different movements. He added that the device “integrates very seamlessly with the physical therapy and occupational therapy that is already offered in clinics, but gives people even more power and more functionality.”

The device may be used to restore other neurological functions, for example: stroke — Dr. Grégoire Courtine, another study author and co-founder of ONWARD Medical, PhD from the NeuroX Institute and Brain Mind Institute, Department of Life Sciences, Swiss Federal Institute of Technology (EPFL) in Geneva, told a press conference.

The company announced on its website that it has received Breakthrough Device Designation status from the U.S. Food and Drug Administration (FDA) for its ARC-EX platform for use in bladder control and cystitis relief. spasticityblood pressure regulation in SCI patients.

Corteen said the company has filed a De Novo application with the FDA seeking regulatory approval for the device, and plans to follow that up with a regulatory filing in Europe.

The company is also researching an implantable neurostimulator, which involves implanting a pulse generator and lead near the spinal cord, and the system could activate nerves more directly than external devices. Corteen said the company plans to begin a pivotal clinical trial of its implantable platform in the United States early next year.

The trial was sponsored by ONWARD Medical, which provided equipment and field support to the researchers. The researchers hold various patents related to their current research, serve as consultants to Onward Medical, and may be minority shareholders in Onward Medical.