If any of the following flags are seen in a patient with low back ache, imaging with MRI is recommended. CT only if MRI is contraindicated.
| cauda equina syndrome (urinary retention, faecal incontinence, saddle anesthesia) |
| severe unremitting worsening of pain at night – infection or tumor |
| significant trauma – fracture |
| unexplained weight loss, fever, HIV, history of cancer – infection or tumor |
| use of intravenous drugs or steroids – infection or compression fracture |
| widespread neurological signs – tumor or neurological disease |
| >50 years, particularly >65 years with new onset back pain |
| duration > 6 weeks |
| prior surgery |