Viscosupplementation agents are preparations that have hyaluronic acid, which is injected into the knee joint to relieve pain associated with osteoarthritis. Joints affected by osteoarthritis have less hyaluronic acid, which is naturally present in the synovial fluid. Hyaluronic acid acts as a lubricant and allows bones to move smoothly without rubbing against each other. Viscosupplementation agents also improve joint movement.