Low Back Pain and Red Flags
Pain from the spine's muscles, discs and facet joints is usually a benign, self-limiting mechanical process, but the same anatomy can be compromised by fracture, infection, malignancy or nerve root/cauda equina compression, so every assessment is really a search for the minority who need urgent action.
First principles
Most back pain is mechanical strain of a normal, resilient structure
The lumbar spine is a load-bearing structure of vertebrae, intervertebral discs, facet joints, ligaments and paraspinal muscles, all of which are subject to everyday mechanical stress and minor injury. In the great majority of presentations, pain arises from strain or minor derangement of these structures with no serious underlying disease, follows a benign course, and improves within weeks with simple analgesia and continued activity. Because this 'non-specific' mechanical pain is so common, the clinical task is not to name the exact strained structure but to actively screen for the much smaller group of patients whose pain has a dangerous cause.
Educational content pending clinical review. Not medical advice.