Acute low back pain can be caused by pathology, but this is very rare. 

Red flags are a well-established screening mechanism but many commonly used flags do not meaningfully increase the likelihood of pathology being present.

Screening for pathology also has negative side effects. These include significant radiation exposure, anxiety due to expectation of pathology or incidental findings, and unnecessary subsequent interventions.

“I now (long pause) try to see that in perspective of the harm that you cause by trying to exclude serious pathology all the time”


It is important to differentiate between pathology which requires immediate action in order to change patient outcome (e.g. cauda equina syndrome, infection, abdominal aneurysm), and pathology for which delaying identification by a few weeks will not significantly affect the outcome (e.g. compression fractures, spinal metastases, ankylosing spondylitis).

Although it is important that prolonged treatment is not inappropriately directed at pain of pathological origin, the relative risk of missing these conditions is low compared to the risks of excessive screening.