By Pat Anson, Editor

A two-year study of an innovative spinal cord stimulator shows the device is more effective at relieving chronic back and leg pain long term than traditional stimulators.

The Senza HF10 spinal cord stimulator uses high frequency pulses of 10,000 Hz to mask a patient’s perception of pain. Traditional stimulators typically use lower frequencies at 40 to 60 Hz.  

Spinal cord stimulators (SCS) are often considered the treatment of last resort for chronic back and leg pain, because the devices have to be surgically placed near the spine and connected to batteries implanted under the skin. The devices send electrical impulses into the spine to mask pain.

In a study of 171 patients with implanted SCS devices, 76% of those with back pain and 73% with leg pain had pain relief after 24 months with the Senza HF10. That compares to about 50% of the patients implanted with a traditional stimulator.

The Senza stimulator is made by Nevro Corp. (NYSE: NVRO) a medical device company in Redwood City, California.

"By demonstrating a significant and durable decrease in back and leg pain over a two-year period, Nevro's HF10 therapy represents an important and evidence-based advance in pain medicine,” said Leo Kapural, MD, the lead author and principal investigator of the study, which is published in the journal Neurosurgery.  

“Extending comparative safety and efficacy outcomes from 12 to 24 months provides physicians, patients, and payers with rigorous evidence demonstrating the durability of SCS in treating chronic pain.”

The Senza SCS was approved by the Food and Drug Administration last year. It has been available in Europe and Australia for several years.

Nevro says the HF10 stimulator is the only SCS therapy that provides pain relief without paresthesia -- a tingling or buzzing sensation that lower-frequency stimulators use to help mask pain signals. Some patients have found paresthesia uncomfortable.

MarketsandMarkets, a market research firm based in Dallas, estimates the global market for spinal cord stimulators and other neuromodulation devices could reach $6.8 billion by 2017.