Animal Models of Bone Marrow Lesions in Osteoarthritis

Abstract

Bone marrow lesions are abnormalities in magnetic resonance images that have been associated with joint pain and osteoarthritis in clinical studies. Increases in the volume of bone marrow lesions have been associated with progression of joint degeneration, leading to the suggestion that bone marrow lesions may be an early indicator of-or even a contributor to-cartilage loss preceding irreversible damage to the joint. Despite evidence that bone marrow lesions play a role in osteoarthritis pathology, very little is known about the natural history of bone marrow lesions and their contribution to joint degeneration. As a result, there are limited data regarding the cell activity within a bone marrow lesion and any associated bone-cartilage cross-talk. Animal models provide the best approach for understanding bone marrow lesions at their early, reversible stages. Here, we review the few animal studies of bone marrow lesions. An ideal animal model of a bone marrow lesion occurs in joints large enough to accurately measure bone marrow lesion volume. Additionally, the ideal animal model would facilitate the study of bone-cartilage cross-talk by generating the bone marrow lesion immediately adjacent to subchondral bone and would do so without causing direct damage to neighboring soft tissues to isolate the effects of the bone marrow lesion on cartilage loss. Early reports demonstrate the feasibility of such an animal model. Given the irreversible nature of osteoarthritic changes in the joint, factors such as bone marrow lesions that are present early in disease pathogenesis remain an enticing target for new therapeutic approaches.

Meteorological Influence as an Exacerbating Factor in Knee Osteoarthritis: A Prospective Longitudinal Study

“…This absence could be attributed to the fact that observable bone marrow alterations necessitate substantial and prolonged effects of pathogenic factors [34]. For example, in animal models of KOA, bone marrow injury only manifested at least 2 weeks post interventions like anterior cruciate ligament (ACL) surgery [35]. However, the weatherl data collected in this study was limited to the three days preceding the investigation, possibly insu cient to induce changes in the bone marrow level.…”