Observation and measurements for low back pain evaluation include:

• Observing how you move and walk to see whether you limp or show other signs of pain or leg weakness.
• Looking at the shape of your back to check for uneven bone development or position, differences in leg lengths, and exaggerated curvature of the spine.
• Tapping on (percussing) the spine. If you feel pain when your spine is tapped, you may have a fracture, an infection at or near the site of tenderness, a tumor, spondylolisthesis, or inflamed facet joints or sacroiliac joints.
• Measuring how much your chest expands when you breathe in, especially if you are age 20 to 40 (particularly males because they are at highest risk for ankylosing spondylitis). If you are unable to expand your chest normally when you fully inhale, you may have a form of inflammatory arthritis. These forms of arthritis may affect the places where the ribs attach to the back and the breastbone and make it hard to fully expand your chest when you breathe.