What are supartz (hyaluronic acid) injections used for arthritic knee joint ?

Can help reduce pain: Supartz (hyaluronic acid) is a form of viscosupplementation. There are many chemicals used :synvisc, orthovisc, Hyalgan and others. These are chemical substances that are similar to the cartilage of the knee. Some are totally synthetic and one is from the comb of a rooster. They are used as a single or series of injections into the knee to relieve pain and improve function. They are inert and have no side effects.