Last week, we started this series on common myths and misconceptions around back pain. The first of these was that back pain is something to be dreaded, a dire, unusual event which is likely to progress to prolonged suffering and disability. We know that this is just not true. Back pain is normal; most people will experience it, often many times in their life, and just about everyone recovers from it fairly quickly.
Today, we’re going to look at the use of scans in the diagnosis of back pain. Typically, scans are ordered to help figure out why people are experiencing back pain. Often these scans will come back with evidence of bulging or herniated discs, arthritic changes and other signs of spinal deviation. Patients are then invited to look at these images and advised that the source of their pain is structural. There it all is in black and white.
The trouble is, the kinds of spinal “abnormalities” which show up on scans are known to correlate very poorly with pain. Put another way, people with bulging and herniated discs or other spinal degradation very often experience no back pain at all. If you have these things they may not have anything much to do with the pain you are feeling.
When it comes to scans it’s not just this issue of false positives that creates problems. Once people get it into their heads that some kind of structural abnormality is behind their back pain it’s unlikely that they will look for other solutions beyond medication and surgery. That’s a shame, because there is good evidence that many forms of therapy can help a great deal even when scans show degenerative changes in the spine. These include soft tissue work, pain education, graded movement and appropriate exercise.
There is another consequence of being told by a doctor that evidence from scans shows permanent changes in the bones of the back. These patients recover less well from episodes of back pain than those who don’t have scans or aren’t given scan results even when the structural issues are the same. Telling someone their vertebrae are crumbling or that they have bulging discs adds considerably to their distress and lowers their expectation of a good outcome. What people think is an important factor in pain experiences, especially in chronic pain, and negative beliefs and expectations are likely to lead to protective guarding and avoidance behaviours which can make pain worse or delay recovery.
When it comes to back pain, interpreting scans needs to come with a health warning.