People with chronic back pain have found relief with a pacemaker-like implant that buzzes their muscles twice a day with electrical pulses.
In a year-long trial led by an NHS trust in London, half the patients receiving the treatment reported significant improvements in their pain, disability and quality of life.
Back pain is Britain’s biggest cause of disability, affecting almost a tenth of the population and consuming 1.7 per cent of GDP, according to some estimates.
While the condition can be treated with surgery if it has a specific cause, such as sciatica or a herniated disc, for millions of people there are few options beyond painkillers, exercises and psychological therapies.
Researchers speculated that by using electrodes to zap a branch of the spinal nerve near the L2 vertebra — to make the lumbar multifidus muscle squeeze repeatedly — they could provide long-term pain relief by honing motor control in the lower back.
A group run by Vivek Mehta, consultant in pain medicine at St Bartholomew’s Hospital in the Barts Health NHS Trust, recruited 53 patients aged from their mid-thirties to mid-fifties at nine centres in Europe and Australia.
The participants had the ReActiv8 pacemakers inserted beneath their skin, where the machines made the muscle contract for half an hour each morning and evening. After three months the average pain score had improved by a third, and the effect lasted throughout the year of the trial.
At the end, more than 80 per cent of the patients said that they were happy with the therapy, which will now be tested against placebos in a trial involving 128 people.
Dr Mehta said that after three or four years with the pacemaker, which does not interfere significantly with daily activities, patients should have enough strength in the muscle to come off the treatment. “The data that I’m presenting is that the patients are quite satisfied with the level of stimulation and they can carry on with their work as they would normally do,” he said.
The results were selected yesterday as being among the winning studies at the International Neuromodulation Society’s world congress in Edinburgh. They will be published in a medical journal soon.
Timothy Deer, president of the society and clinical professor of anaesthesiology and pain medicine at West Virginia University, said that nerve-stimulation devices were emerging as a powerful category of medicine.
“We’ve had such great advances,” he said. “In the last five years, the amount of [high-quality] evidence for neuromodulation has been phenomenal. We’ve had new frequences, new targets and new waveforms, and all these have shown evidence of benefit.”
While Professor Deer was initially sceptical when he heard what Dr Mehta’s group proposed to do, he said that he had been won over by their data.
“This type of new technology is exciting for the field and for patients,” he said. “Some of these patients can’t work or spend time with their families, so this is about changing their lives as much as about reducing their pain.”