The natural history of Modic changes in a community-based cohort.

BACKGROUND: Vertebral endplate (Modic) lesions are gaining interest, with varied phenotypes recognised to have distinct clinical and histological correlates. Nevertheless, the natural history of these lesions is unclear. This study examined the natural history of Modic changes and their potential relationship to the intervertebral disc.

METHODS: Seventy-two community-based adults not selected for low back pain had lumbar spine magnetic resonance imaging (MRI) performed at baseline (2012) and approximately 2 years later to assess Modic lesions. Fifty-six participants completed the study. Intervertebral disc pathology was assessed by disc height and the Pfirrmann grading system at baseline.

RESULTS: At baseline, 6 Modic type 1 lesions were present in 3 (4.2%) participants. At follow-up, 4 persisted, 2 changed to a Modic type 2 lesion, and there were 4 incident lesions. Only 1 participant (1.4%) had a baseline Modic type 3 lesion, which persisted at follow-up, with one further incident lesion. Modic type 2 lesions were most common (n=47, in 20 of 72 [27.8%] participants). Resolution of Modic type 2 lesions was uncommon (n=1, with 2 changing to a type 1 lesion). 18 incident lesions occurred in 7 (12.5%) participants, with most occurring both sides of the intervertebral disc. A reduction in the average baseline disc height was associated with an increased risk for type 2 incident lesions (OR 1.9, 95% CI 1.1 to 3.3, P=0.03). Similarly, severe baseline disc degeneration at L3/4, L4/5 and L5/S1 was associated with an increased risk for type 2 incident lesions (all P≤0.05).

CONCLUSION: This longitudinal study has demonstrated that Modic type 2 are the most common of the Modic lesions in community-based adults and while resolution of these lesions is uncommon, incident disease develops on both sides of the intervertebral disc in the setting of severe disc degeneration. These results suggest that type 2 Modic changes are a sequel of disc degeneration.