Bone structural changes in osteoarthritis as a result of mechanoregulated bone adaptation: a modeling approach

Objective: There are strong indications that subchondral bone may play an important role in osteoarthritis (OA), making it an interesting target for medical therapies. The subchondral bone structure changes markedly during OA, and it has long been assumed that this occurs secondary to cartilage degeneration. However, for various conditions that are associated with OA, it is known that they may also induce bone structural changes in the absence of cartilage degeneration. We therefore aimed to investigate if OA bone structural changes can result from mechanoregulated bone adaptation, independent of cartilage degeneration. Method: With a bone adaptation model, we simulated various conditions associated with OA -without altering the articular cartilage- and we evaluated if mechanoregulated bone remodeling by itself could lead to OA-like bone structural changes. Results: For each of the conditions, the predicted changes in bone structural parameters (bone fraction, trabecular thickness, trabecular number, and trabecular separation) were similar to those observed in OA. Conclusion: This indicates that bone adaptation in OA can be mechanoregulated with structural changes occurring independent of cartilage degeneration. (C) 2011 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.