Synvisc is a sterile, non-pyrogenic, elastoviscous fluid containing hylan. Hylan is a derivative of hyaluronan, which is responsible for the elastoviscosity of synovial fluid in the joints. With this, Synvisc injections may be used as a temporary replacement and supplement for synovial fluid. Synvisc achieves its therapeutic effect through viscosupplementation, a process whereby physiological and rheological states of the arthritic joint tissues are restored. Viscosupplementation with Synvisc decreases joint pain and discomfort, allowing more extensive movemen