Investigation Strategies

No investigation is required for the vast majority of patients with non-specific back pain. Red flag symptoms or signs suggestive of cauda equina syndrome will mandate urgent MRI scanning.

Imaging of patients with non-specific back pain and no red flag symptoms or signs is unhelpful. Many patients with spinal pathology may have normal plain X-rays and, conversely, many patients with no back pain may have X-ray abnormalities (particularly degenerative disease). Similarly many patients with no back pain have abnormal MRI scans.

Blood tests may be useful if one suspects infection or metabolic problems but are not necessary as screening investigations for patients with no pointers to those problems.

In primary care, radiography of the lumbar spine in patients with back pain of more than six weeks duration improved patient satisfaction but did not improve outcome.⁶ There is no published evidence on the value of X-rays in the acute setting but the inference is that there is no benefit.⁷