Associations between high intensity zones, Modic and endplate changes in lumbar spine of low back pain patients
Abstract Background High intensity zones (HIZ), Modic and endplate changes have all been pointed out as potential markers of low back pain (LBP). If an association between these morphological features exist, it may not only deepen the understanding of the underlying patho-physiological mechanism of LBP but may also improve the diagnostics by enabling stratification between individuals with non-specific LBP as well as within individuals having multi-segmental changes. The aim was to investigate if HIZ, Modic and endplate changes are associated and if endplate and vertebral T2-values reflect functional tissue characteristics related to these morphological features.Methods 150 IVDs with corresponding endplates and vertebrae in 26 chronic LBP-patients (25-69y, mean 38y, 11 males) were examined with T1- and T2-weighted MRI, and T2-mapping. Associations between morphological features and between morphological features and functional T2-values were determined. Results HIZ (62% of patients, 1-2/patient) was associated with endplate changes (100% of patients, 1-7/patient) (p=0.0003 and 0.0004 for upper and lower endplates), with an occurrence of 91% for upper and 71% for lower endplates adjacent to discs with HIZ. Modic changes (81% of patients, 1-3/patient) was associated with endplate changes (p<0.0001) with an occurrence of 87% for endplates adjacent to vertebrae with Modic changes. The occurrence of both HIZ and Modic changes was 43% (p=0.0001) for upper and 29% (p=0.003) for lower vertebrae. Significantly higher T2-values (p<0.004) were found in the vertebral tissue with associated Modic changes and HIZ. Conclusions This study of LBP-patients suggests that HIZ is associated with simultaneous presence of both Modic and endplate changes in the same motion segment. If these three simultaneous morphological features are linked to an active inflammatory process, reflected as a clinical specific pain profile remains to be investigated.