Recent progress toward biomarker identification in osteoarthritis.

Osteoarthritis (OA), the most common and disabling form of arthritic disease, is characterized by a slow and progressive degeneration of articular cartilage. Its etiology is multifactorial and includes genetic predisposition, obesity and aging. In addition to the cartilage itself, OA also involves the surrounding tissues, including the synovium and the subchondral bone. This clinical heterogeneity complicates the identification of biomarkers that are crucial for prompt pharmacological intervention at the early stages of the disease and for monitoring treatment efficacy with higher sensitivity than existing imaging methods. In this review, we highlight the difficulties associated with OA diagnosis and discuss the most recent research efforts and successes for the identification of reliable OA biomarkers.