By Liam Mannix
An alien device resides inside Marcus Barlow’s skin. Its metal wiring runs up and down his back, intertwining with delicate nerves.
Its bulky sarcophagus presses against his spine when he tries to lie down to rest, the sharp pain refusing to let him sleep, until he finally contorts himself on his side.
“It’s a travesty they did this to me,” Barlow says. “It digs into me all the time. It has been an absolute nightmare.”
Marcus Barlow says his spinal cord stimulator has been “an absolute nightmare”. Credit: Simon Schluter
Barlow is one of thousands of Australians who have received spinal cord stimulators: expensive electrical devices, wired into the nerves, and touted as a cure-all for chronic back pain.
That was before a 2022 investigation by this masthead revealed serious questions about the devices’ effectiveness and safety records. Academics around the world are now working to answer those questions – leading to the publication of the largest-ever study of spinal cord stimulators in the Medical Journal of Australia this week.
Some of the findings are not good for the multibillion-dollar industry.
The new study found 23 per cent of patients who get a stimulator will need revision surgery – most within 18 months.
Due to the short time frame, the researchers think these re-operations are likely from complications with the device, like malfunction. The number does not include operations to fix device wires moving in the back, one of the most common complications.
Total knee replacements, by comparison, have a lifetime surgical re-operation rate of around 2 per cent.
The evidence is now clear, says lead-author Dr Caitlin Jones, from the University of Sydney’s Institute of Musculoskeletal Health: the risk posed by the devices is much greater than the likely benefits.
“Patients should know they are taking on a substantial risk, that is exorbitantly expensive, with very little likelihood of any benefit.”
The Medical Technology Association of Australia (MTAA), which represents device manufacturers, rejected Jones’ claims. Stimulators were “a demonstrably safe and effective alternative to long-term drug therapies, notably opioids”, a spokesman said.
“[Stimulator] suppliers stand behind the safety, quality and efficacy of our SCS technologies that have demonstrated positive outcomes for patients, which are backed by robust clinical trial data and real-world evidence.”
An X-ray showing a spinal cord stimulator implanted in a patient.
Spinal cord stimulators consist of a small battery pack, implanted beneath the skin, attached to several electrodes. In theory, pulses of electricity interfere with pain signals coming from the nerves. Manufacturers say they are “proven safe and effective”.
Chronic pain, and chronic pain following back surgery – a horror condition known as “failed back surgery syndrome” – are difficult to treat, pushing pain doctors to reach for solutions with weaker evidence bases. “Nothing in pain management has bulletproof evidence,” said Associate Professor Michael Vagg, director of professional affairs for the Australian Faculty of Pain Medicine.
But Cochrane reviews of the evidence – generally viewed as gold-standard scientific evidence and designed to be free of industry-funded bias – have concluded the devices are likely not helpful for people with chronic pain or back pain.
“We are talking about an ineffective treatment,” said Associate Professor Adrian Traeger, a University of Sydney academic who led one of the reviews.
“People are accepting these high costs and risks for a treatment that was proven no better than placebo. Why?”
He said the fact patients continued to receive stimulators suggested “the risk versus benefit profile is not being fully explained to patients”.
Australia’s pain management faculty does not have a position on stimulators, but Michael Vagg said he used them on a small group of patients in his practice “with generally good to excellent results”.
“Stims are never going to be suitable for even a sizeable minority of pain patients,” he said.
The MTAA said the Medical Journal of Australia study overlooked “the broader landscape of robust clinical evidence and real-world patient outcomes that support the use of spinal cord stimulation”.
Marcus Barlow struggled with low back pain for years.Credit: Simon Schluter
Private Healthcare Australia helped facilitate the insurance data used in the Medical Journal of Australia study, but did not fund it. “This is a very expensive procedure which study after study after study shows does not work any better than placebo,” said Ben Harris, the organisation’s director of policy and research.
On average, each patient receiving a stimulator cost private insurers $55,635, plus out-of-pocket costs for the patient, the study found.
The MTAA said the fact private insurers had supplied the data – when they had an interest in avoiding paying for stimulators – potentially biased the outcome.
And the researchers data did not tell them why the re-operations were being performed. “Drawing significant conclusions without understanding the clinical justifications for these procedures is misleading.”
The association also decried the Cochrane reviews, which it said were “widely criticised”.
Marcus Barlow received his stimulator after struggling for decades with chronic lower back pain. “You’d do anything,” he said.
Barlow remembers being surprised a representative from the manufacturer of his stimulator was in surgery with him. He also remembers waking up in agony. “My leg, it was almost like it was on fire,” he said.
Things did not improve. Barlow regularly returned to the doctor for adjustments to the stimulation. “I was kidding myself it worked. It never worked. It never helped me at all,” he said.
Following a review triggered by this masthead’s 2022 investigation, the federal Department of Health launched a review of spinal cord stimulators. In August last year the Therapeutic Goods Administration cancelled the registrations of 12 of the devices and imposed conditions on another 52.
The review is ongoing. A spokesman for the TGA said the “evidence reviewed by the TGA indicates an acceptable risk-benefit profile”.
What does work for chronic back pain?
If you have chronic back pain and don’t want to get a spinal cord stimulator, there is a range of other evidence-based options, said Professor Chris Maher, director of the Institute for Musculoskeletal Health.
Trying to increase the amount you exercise and following a healthy lifestyle was a simple cornerstone treatment. A 2021 Cochrane review found moderate-quality evidence exercise improved back pain more than a placebo.
Chronic low back pain has a significant neurological component. Psychological treatments, particularly cognitive behavioural therapy, has been shown to be effective.
The most cutting-edge treatment is known as cognitive functional therapy: a combination of physical and mental therapies designed to rebuild the brain’s connection with the back. A course of eight CFT sessions with a physio costs less than $1000.
“Spinal cord stimulators are 50 times this price,” said Maher. “And they do not work.”
Liam Mannix is the author of Back Up: Why back pain treatments aren’t working.
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correction
Michael Vagg is from the Australian Faculty of Pain Medicine, not the Australian Faculty of Pain Management.