TO SCAN OR NOT TO SCAN
MANY patients seek an MRI scan, believing it will identify the cause of their pain.
But while a scan might pick up spinal abnormalities, chances are these won’t be the cause of the pain. Most people’s spines over the age of 40 show signs of degeneration, so a scan is highly likely to produce red herrings.
‘I tell my patients that having a scan on your back is a bit like having a survey done on a house,’ says physiotherapist Laura Finucane.
‘It’s going to throw up all sorts of things but actually those things probably aren’t going to cause problems.’
Multiple studies have shown that if you scan a group of 50 to 60-year-olds who don’t have back pain, half of the scans show abnormalities.
‘So if you then scan 100 people who have got pain, how do you know the findings on their scans are relevant, when someone else who doesn’t have pain has the same abnormalities?’ asks consultant spinal surgeon Lee Breakwell.
What a scan reveals and how much pain a patient is in ‘have absolutely no correlation’, confirms Arun Bhaskar, a consultant in pain medicine at Imperial College Healthcare NHS Trust and president of The British Pain Society.
‘You can have a pristinelooking spine yet have severe pain, or a spine that looks like it was run over by a train several times but you have no pain,’ he says.
The consensus is that scans should not be used as an investigative tool, but only to confirm a diagnosis.
In fact, as well as rarely being necessary, MRI scans can make things worse because, as Laura Finucane explains, ‘you end up worrying the patient unnecessarily’.
‘ They think something terrible is happening to their back and then you see a downward spiral — they stop moving, lose flexibility and muscle tone and that can only add to their pain,’ she says.
A study of 246 patients with back pain and sciatica, published in the American Journal of Neuroradiology in 2008, found those given their MRI results did not improve as well as those not given them. X- rays are no more beneficial. In 2001 a study in The British Medical Journal of 421 patients who’d had back pain for ten weeks or more showed conclusively that use of X-rays ‘is not associated with improved patient functioning, severity of pain, or overall health status’. However, it was ‘associated with an increase indoctor workload’.