New Wearable Devices for Chronic Pain

By Pat Anson, Editor

With opioid pain medications becoming harder to get and many patients looking for safer alternatives with fewer side effects, a growing number of companies are offering wearable “electrotherapy” devices for pain relief.

There’s the Cefaly headband for migraines, ActiPatch for sore muscles, AcuKnee for osteoarthritis, and the Quell nerve stimulator, which is designed to treat a range of chronic pain conditions. All are part of a fast growing $2.8 billion market for wearable medical devices.

“There’s a big problem brewing on the horizon. And that is the pain medications are being removed from the market, slowly but surely,” says Phillip Muccio, President and founder of Axiobionics, which has been making customized electrotherapy devices for 20 years.

“Electrical stimulation has a way of reaching into the body and interacting and coordinating what happens to the body. That’s why it a fascinating area of medicine because not a lot of things will do that, especially non-invasively and non-pharmacologically.”

Most of the new devices use a form of electrical stimulation to block or mask pain signals – a technique developed decades ago known as Transcutaneous Electric Nerve Stimulation (TENS).

Unlike the old TENS units, which are typically used for about 30 minutes, wearable devices are designed to be worn for several hours at a time or even while sleeping.

 image courtesy of axiobionics

image courtesy of axiobionics

“TENS is like a short acting opioid. It’s basically only effective when it’s on,” said Shai Gozani, MD, President and CEO of Neurometrix. “If you’re going to deal with chronic pain, you have to have a wearable, chronically usable device, because pain can be two hours a day or it could be 24 hours a day. TENS devices historically haven’t been designed at all for wear-ability or continuous use.”

Neurometrix recently introduced Quell, an electrotherapy device that Gozani compares to a spinal cord stimulator. But instead of being surgically implanted near the spine like a stimulator, Quell is worn externally on the upper calf below the knee.

 image courtesy of neurometrix

image courtesy of neurometrix

“We really look at spinal cord stimulation as the model. We’re trying to make that available but in a non-invasive, wearable way -- versus TENS devices which are really intended for local muscle stimulation. We don’t stimulate the muscles, we stimulate the nerve alone,” Gozani told Pain News Network.

“The upper calf has a lot of nerves. It’s comfortable. It’s discrete. So it meets the requirement to have a large segment of nerves to stimulate, but it’s also highly usable from a wear-ability perspective.”

A small study recently conducted by Neurometrix found that over 80% of Quell users had a significant reduction in pain and two-thirds were able to reduce the amount of pain medication they were taking.  Participants in the study had several different types of of chronic pain, including fibromyalgia, sciatica, neuropathy and arthritis.

When it comes to clinical studies, medical device makers have a clear advantage over pharmaceutical companies, which often have to spend years and tens of millions of dollars proving the safety and effectiveness of their drugs before they’re approved by the Food and Drug Administration. Device makers are held to a lower regulatory standard.

“Devices are approved by FDA basically for safety and not necessarily for efficacy. It’s a lot easier to demonstrate that with a device than if you have to demonstrate a new drug. You basically run one study or two and show that nobody got electrocuted by a TENS unit and you’re good to go,” said Bob Twillman, PhD, Executive Director of the American Academy of Pain Management.

Device makers can even get fast track approval from the FDA without any clinical studies -- if they say a new device is substantially equivalent to an older device already on the market.  Quell, for example, was given clearance by the FDA because of its similarity to Sensus, another Neurometrix device that's worn below the knee for pain relief.

A significant disadvantage for device makers is that most are not covered by public or private health insurers – meaning patients have to pay for them out of pocket. Three years ago, Medicare stopped covering TENS for low back pain, saying the technology was “not reasonable and necessary.”

The lack of reimbursement also makes many doctors unwilling to prescribe wearable devices and unfamiliar with the technology behind them, which stifles innovation.  For that reason, Neurometrix took an unconventional path and made Quell available without a prescription – bypassing insurers and doctors so it could market directly to consumers for $249 a unit.

“We thought it was imperative to get it over the counter. We wanted to make sure it was accessible to patients," said Gozani. "Wear-ability changes everything. Wear-ability is the game changer in terms of optimizing pain relief. I think it's huge."