It is one of the most common medical conditions in the world - yet we often don’t know what causes it, nor how best to treat it
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Hello, and welcome back to Everyday Science.
You may have seen articles this week saying that most non-surgical back pain treatments – like painkillers and heat treatments – don’t work very well.
As someone who has had back trouble myself, this is a subject I have been following keenly, since my first spasms of agony five years ago, after foolishly picking up something really heavy. (An enormous home-grown pumpkin, if you’re curious.)
The bad news, I’m afraid, is that, it’s not just the drugs that don’t work. Even when considering spinal injections and other interventions for back pain, there is conflicting evidence about whether they help.
So why is it so hard for doctors to help people with back pain? And what do we know about what does and doesn’t help?
Back pain is certainly a huge problem. It is one of the most common medical conditions in the world, with an estimated six in 10 people experiencing it at some point in their lives.
There are many different possible causes. Less serious ones include strains of muscles or other tissues, which tend to recover within a few weeks. If the pain persists or is severe, doctors will want to rule out explanations such as a spinal tumour or infection.
But for most people, it is not really clear what the problem is.
Confusingly, many people will have a scan of their back, and are told that it has revealed something wrong with one of their spinal discs.
Discs are soft circles of tissue – about the size and shape of a bathroom sink plug – that cushion the spine’s vertebrae. The most common concerning scan findings are disc degeneration, when they appear worn down, or – as in my case – the dreaded “slipped disc”.
In fact, the disc hasn’t really slipped as such. The discs have a jelly-like filling surrounded by tougher fibrous skin. What really happens is the soft core breaks through that skin and the disc now has a bulging appearance, which can be seen on a scan.
One theory is that the bulging disc presses on nearby nerves, and that’s what leads to those terrible shooting pains. If the sciatic nerve going down into the leg is affected, the pain can radiate all the way down to the foot. Another idea is that the damaged disc releases inflammatory chemicals and that is what causes overactivity of the nearby nerves.
As well as the unhelpful terminology, there’s a more important issue. We don’t even know if a bulging or degenerative disc seen on a scan is really the cause of the back pain at all.
When doctors do scans on people without back pain, they find the appearance of disc-bulging or degeneration in as many as a third of people. This suggests that if you do have back pain and a scan reveals degeneration or bulging, that isn’t necessarily the cause of the pain.
Absence of evidence
If we don’t know what is causing the pain, it becomes less surprising that we don’t have very good ways of treating it. And that is what was found by the latest study, which was published in BMJ Evidence-Based Medicine.
The researchers looked at the evidence for 56 different treatments or treatment combinations available for back pain, either of new-onset or of long-term.
For new-onset pain, the only treatment found to help was a group of medicines called non-steroidal anti-inflammatories (NSAIDs). These include ibuprofen and prescription drugs like diclofenac.
For long-term (or chronic) pain, several things were found to help, including exercise, spinal manipulation, taping and antidepressants. But these only gave small reductions in pain.
There was no good evidence found to support injections of steroids into the spine, which are usually the option that doctors offer if people’s pain cannot be controlled with medicines like NSAIDs.
This is not the first research to cast doubt on their effectiveness. Last month, another review specifically looking at spinal injections of steroids or local anaesthetics found they give little to no pain relief.
The findings came as no surprise to Professor Jane Ballantyne, an anesthesiologist at the University of Washington. “The majority of back pain doesn’t really have a ‘pain generator’ that you can easily fix,” she said.
On the other hand, Dr Rajesh Munglani, who is vice-president of the British Pain Society, said that the recent papers casting doubt on spinal injections were flawed because they lumped together all people with backache, when injections may help carefully selected patients.
“We’ve got to develop guidelines which work for individual patients, rather than just saying, ‘this works, that doesn’t work’, because that doesn’t tell you what’s going to happen in the individual,” he said.
Vicious circle
It is hard for patients to know what to do because there is clearly disagreement among the experts. Professor Ballantyne has long argued that doctors are too keen to treat pain with drugs and injections, and that we ignore the psychological aspects of long-term pain, such as how it can cause depression and interfere with sleep, in a vicious circle.
“There are two components to all pain,” she said. “One of the components is the way it’s processed in the brain. And that component is actually quite amenable to thinking differently about it, accepting it, and making general efforts towards wellness.”
That chimes with the growing drive among health services to offer chronic pain patients psychosocial approaches like talking therapy, antidepressants and practical advice on how to maintain exercise levels. Exercise was one of the few interventions that did get a positive result in the most recent review of the evidence, at least for long-term back pain (but not new-onset pain).
And yet, as someone who could at times in the past few years have been classed as a chronic pain patient, I can vouch that, ironically, there is nothing more depressing than hearing you are expected to manage your pain through “psychological approaches”.
There is no need to feel sorry for me, though, as I am one of the fortunate people whose back pain did eventually recede without needing any drastic interventions like injections or surgery.
Perhaps it was because I followed my physiotherapist’s exercise advice or perhaps my back just got better by itself over time. I guess I’ll never know. But I would love to hear from you, if you have also wrestled with back pain.
I’ve also written…
Depression is another medical condition where current treatments don’t work for everyone. Now, a large real-world study has identified the groups of people who are least likely to find them helpful – and those who are most likely to benefit.
I’m reading…
The List of Suspicious Things, a debut novel from Jennie Godfrey, is about two Yorkshire schoolgirls, set during the activities of the serial killer known as the Yorkshire Ripper, in the 1970s. Fortunately, the book is not about the horrific murders, but about the girls’ intriguing relationships with each other and their complicated families.