Diagnostic evidence in suspected discogenic low back pain: a pain-source attribution perspective

Discogenic low back pain (DLBP) remains difficult to identify clinically because degenerative disc changes are common and symptom patterns overlap with other lumbar or pelvic pain sources. This mini review summarizes evidence relevant to suspected DLBP from a pain-source attribution perspective, focusing on clinical features, disc and endplate magnetic resonance imaging (MRI) findings, assessment of other pain sources, provocative discography, and diagnostic blocks. Clinical features such as axial low back pain, sitting or flexion intolerance, non-radicular referral, and centralization may increase suspicion of disc-related pain, but they have limited specificity when used alone. MRI can identify high-intensity zones, Modic changes, and other disc- or endplate-related abnormalities that support structural compatibility when findings correspond to the suspected level. Assessment of other pain sources helps refine the differential diagnosis and reduces overinterpretation of disc-related imaging findings. Provocative discography and diagnostic blocks provide procedural information through reproduction of familiar pain and pain change after targeted anesthesia, respectively, but these responses require interpretation alongside clinical and imaging evidence. Overall, suspected DLBP is more strongly supported when clinical presentation, level-concordant imaging findings, assessment of other pain sources, and procedural responses point in the same direction within the same patient. Future studies should evaluate whether combined diagnostic information improves diagnostic agreement and patient selection for further diagnostic evaluation.