Chronic back pain is linked to physical changes in the brain, according to researchers in Germany.
A team found patients with the condition also had microstructural changes in the pain-processing areas of their brains.
The scientists said the work provided evidence that the condition was real and it could aid treatment research.
The research was presented at the Radiological Society of North America's annual meeting, in Chicago.
To study the condition, the researchers used a technique called diffusion tensor imaging (DTI) to look at the differences between sufferers' and healthy volunteers' brains.
They discovered the brains of patients with chronic back pain had a more complex and active microstructure compared with the healthy volunteers' brains.
The changes occurred in regions of the brain associated with pain-processing, emotion and stress response.
Source - BBC