The association of Modic changes with severe and disabling low back pain: a large-scale, population-based study

Abstract

Objective: There is lack of information about severe or disabling low back pain (LBP) and Modic changes (MC). Our aim was to study the relationship of prolonged severe or disabling LBP with lumbar MC focusing on morphology of MC. Methods: Our cross-sectional study comprised of Southern Chinese volunteers. MC and disc degeneration (DD) were assessed from axial T1- and sagittal T2-weighted lumbar MRIs (3T). Prolonged severe LBP (LBP lasting ≥30 days in the past year and intensity ≥6 out of 10-cm VAS) and disabling LBP (Oswestry Disability Index ≥15%) were used. Logistic regressions (adjusted for age, gender, lifestyle covariates, and DD) were used. Results: There were 1,546 subjects (63% females, mean age 53 years) and 21.9% had MC (29.0% ’Type I’, 71.0% ’Type II’). Subjects with MC were older (p=0.002) and had greater DD (p<0.001). In the fully adjusted models, MC in general (OR 1.48; 95% CI 1.01-2.18), MC affecting whole anterior-posterior (AP) length (1.62; 1.04-2.51) and 2/3 posterior length (2.79; 1.17-6.65) were associated with prolonged severe LBP. MC in general (1.47; 1.04-2.10), ‘Type II’ MC (1.56; 1.06-2.31), MC affecting 2/3 posterior length (2.96; 1.27-6.89) and extensive MC (1.95; 1.21-3.15) were associated with disabling LBP. The number of (large) MC strengthened both results. Conclusions: We found MC to be independently associated with prolonged severe and disabling LBP in this large-scale study. The number of MC and larger size (both horizontal and vertical plane) of MC increased the strength of associations. These findings support the hypothesis of clinical importance of MC.