Abstract
Osteoarthritis (OA) involves the loss of the physiological balance between degradation and replenishment of intercellular matrix in the cartilage and other tissues of the joint. This uncoupling eventually results in changes in the structure of the affected joints, which may cause pain and physical disability. OA evolves slowly and is a heterogeneous condition. Concurrent with the slow natural progression of OA, the patient and the joint tissues age, inducing additional and confounding functional changes in the musculoskeletal system. The molecular signals regulating cither the breakdown of the matrix or its replenishment are unknown.