Osteoarthritis (OA) is a degenerative disease associated with the degeneration of the cartilages. In a healthy joint, there is a balance between the production and breakdown of hyaluronic acid, which provides lubricating and protecting properties of the synovial fluid. In a joint affected by OA, hyaluronic acid is being broken down more rapidly than it is produced. Synovial fluid becomes watery and its lubricating and protecting properties are lost. Cartilage in the joint gradually wears off and this causes pain, stiffness and swelling of the joint. Other factors that may lead to OA include aging, gender, weight and previous joint injuries.