Which test is most specific for detecting lumbar radiculopathy?

• A. Crossed Straight Leg Raise
• B. Slump Test
• C. Femoral Nerve Stretch Test
• D. Well Leg Raise

Answer: (A)

When evaluating lumbar radiculopathy, specificity tells you how reliably a positive sign indicates a nerve-root problem rather than another issue. The crossed straight-leg raise stands out because pain in the opposite leg when you raise the other leg is a sign highly specific for a disc herniation irritating a lumbar nerve root on the opposite side. It’s unlikely to be caused by simple hamstring tightness or non-radicular back pain, so a positive result strongly supports radiculopathy rather than other conditions.

A straight-leg raise on the affected side is very sensitive, meaning it often detects radiculopathy but can be positive for several non-radicular problems as well, so it’s less specific. The slump test also screens neural tension but tends to be positive in broader neurodynamic issues and isn’t as specific to lumbar root compression. The well leg raise can mimic radicular symptoms but doesn’t localize the problem as clearly and is less reliable for confirming lumbar radiculopathy. The femoral nerve stretch test targets upper lumbar roots (L2–L4) and anterior thigh symptoms, which is a more specific concern for femoral neuropathy rather than the typical lumbar radiculopathy that presents down the leg.

So the most specific test for detecting lumbar radiculopathy is the crossed straight-leg raise.