Discs, being soft tissues, do not show up on X-rays, but it is often possible to spot disc damage by looking at the size of the spaces between the vertebrae. A narrowed disc will show up on an X-ray as bony vertebrae being closer together than normal. Most of the time, however, X-rays merely exclude more serious damage and do not show up anything useful. In at least 90 per cent of patients X-rays do not provide any positive diagnostic information.