From Modic changes to the disc-endplate-bone marrow complex: imaging stratification, immune remodeling, and translational implications in intervertebral disc degeneration.

Intervertebral disc degeneration (IVDD) is frequently implicated in low back pain (LBP), yet the severity of degeneration on imaging often fails to parallel pain intensity or functional limitation. Modic changes capture abnormal marrow signal at the disc-vertebral interface, but they primarily describe subendplate marrow signal rather than lesion continuity across the disc, cartilaginous endplate, and adjacent marrow. The disc-endplate-bone marrow complex (DEBC) classification provides a complementary lesion-level imaging framework that integrates disc signal, endplate integrity, and adjacent marrow response. By incorporating short tau inversion recovery (STIR) sequences, DEBC may help identify imaging features suggestive of edema-like lesion activity; however, STIR hyperintensity should not be interpreted as direct proof of inflammation, pain generation, or a specific molecular program. This narrative and critical review synthesizes imaging, mechanistic, omics, and translational evidence to evaluate the biological plausibility and current limitations of the DEBC framework. We argue that DEBC should not replace Modic classification, assign pain causality, or guide treatment as a stand-alone criterion. Rather, its current value lies in generating testable hypotheses, improving lesion-level stratification, and supporting future imaging-to-molecular validation. Longitudinal imaging, histopathology, spatial omics, and clinical outcome studies are needed to determine whether DEBC types correspond to reproducible lesion ecologies, pain-associated phenotypes, or treatment-response patterns.