Objective: Bone Marrow Lesions (BMLs) are important in established knee osteoarthritis (OA), predicting pain and progression of disease. Whether BMLs are also associated with longitudinal changes in knee structure in an asymptomatic population is unknown.
Methods: 148 healthy pain free women in middle age with no history of knee injury or clinical knee OA who had an MRI performed on their dominant knee at baseline, had another MRI 2 years later to assess whether having a BML present at baseline affected change in tibiofemoral cartilage defects and tibial cartilage volume.
Results: BMLs were present in 14.9% of women at baseline. The risk of progression of total tibiofemoral cartilage defects was significantly higher where a very large BML was present (OR 5.55, 95% CI 1.04, 29.6) compared to where no BML was present, after adjusting for potential confounders. In the lateral compartment, the rate of cartilage volume loss was significantly greater where a BML was present after adjusting for confounders (Regression coefficient 39.2 mm3 95% CI 11.1, 67.2, p = 0.007).
Conclusions: In healthy women without pain at baseline, large BMLs were associated with both progression of cartilage defects in the whole tibiofemoral joint and more rapid lateral tibial cartilage loss. These data suggest that the relationship between BMLs and knee cartilage in healthy women is similar to that described in established OA. It is possible that BMLs may predict increased risk of knee OA, and facilitate the identification of novel interventions to prevent disease.