Role of Different Pre-Treatments on Composition and Rheology of Synovial Fluids

Different pre-treatments applied to synovial fluids (SF) before their analyses are tested to characterize SF after storage under different conditions and to investigate their evolution along a viscosupplementation treatment. The main techniques proposed involve steric exclusion chromatography with triple detection (SEC) and viscometry; it is the first time that such a study is developed. SEC gives the molecular weight distribution and concentration of hyaluronan (HA) and proteins separately; the steady state viscosity is always non-Newtonian and not directly related to SF composition. Pre-treatment of SF (storage in cold, filtration, centrifugation) allows us to conclude that, in order to store SF, it is best to freeze it, even if in some cases, viscosity is modified but not the composition. All the data obtained (including protease pre-treatment) allow us to conclude that a small fraction of HA-protein complex forms a loose 3D-network and controls the rheology.