Rheological and frictional analysis of viscosupplements towards improved lubrication of human joints

The present paper explores the effect of viscosupplementation on the friction of articular cartilage depending on the rheology of viscosupplements. The experiments were realized on rotational rheometers and a tribometer in pin-on-plate configuration. Five commercially available viscosupplements and their mixtures with synovial fluid were tested. The results showed differences by the order of magnitudes between viscosupplements viscosity and no viscoelastic properties in some of them. The friction was substantially affected by the addition of viscosupplement into the model synovial fluid. In most cases, mixtures of synovial fluid and viscosupplement even showed similar friction as clear viscosupplements. This study is the basis for a better understanding of the short-term changes in articular cartilage frictional behavior after the viscosupplementation of synovial joint.