Chronic low back pain in relation to Modic changes, bony endplate lesions, and disc degeneration in a prospective MRI study

Abstract

Purpose: To clarify the significance of Modic changes, bony endplate lesions, and disc degeneration as predictors of chronic low back pain (LBP) during 1-year follow-up.

Methods: 49 patients with severe, non-specific, chronic LBP, and Modic 1 lesion (M1) were prospectively studied with MRI and questionnaire. Changes in grade of disc degeneration, severity of Modic changes, Schmorl lesions, and bony endplate irregularities were evaluated and changes assessed in LBP intensity on numeric rating scale 0-10 and severity with Oswestry disability index 0-100 (ODI). Association between change in MRI findings and symptoms was computed using generalized estimating equations analysis.

Results: Although pain decreased in most patients during 1-year follow-up, it increased or persisted in 36 %. Change in M1, M2, bony endplate lesions, and signal intensity (SI) and height of the disc associated with change of pain intensity, while change in M1, bony endplate lesions, and disc height associated with change of ODI. Not only persistent M1s, increasing bony endplate lesions, decreasing disc height, and M2s, but also new M2s predicted persistence of pain, while decrease of M1s and SI of the disc and increase of size of M2s predicted decrease of pain. Changes in disc bulges did not associate with pain.

Conclusions: In patients with chronic non-specific LBP, persisting M1, decreasing disc height, and increasing bony endplate lesions associated with persisting pain while decrease of SI of the disc with decrease of pain. Such changing MRI findings in the same disc space have earlier been shown to progress abnormally fast. They may be signs or biomarkers of a prolonged pain causing, deforming degenerative process, and should lead to considering early intervention or specific treatments to affect that process.

Keywords: Intervertebral discs; Low back pain; Magnetic resonance imaging; Modic changes; Prospective study; Vertebral endplate.