A rheological study of treatments for osteoarthritis

Osteoarthritis is a common joint disease causing pain and inflammation that limits mobility and functionality. Osteoarthritis is a widespread disease, and despite it's prevalence there is no cure. The disease progresses by degrading joint cartilage and synovial fluid. The current work aims to contribute to existing knowledge regarding osteoarthritis through three research projects including a rheological study of novel anti-inflammatory hyaluronic acid derivatives, a case study on the effects of oral glucosamine supplementation on synovial fluid viscosity, and development of a microfluidic rheometer that may be used to study low viscosity fluids such as hyaluronic acid and synovial fluid at high shear rates. The anti-inflammatory hyaluronic acid derivative demonstrated shear thinning and viscoelastic behaviour as expected. This behaviour is common among viscosupplements and is therefore promising for it's potential use as a viscosupplement, however, the viscosity and viscoelasticity were significantly lower than commercial viscosupplements. It is recommended to investigate modulating viscosity and viscoelasticity with techniques such as cross-linking and increasing hyaluronic acid concentration. In a patient discontinuing oral glucosamine supplementation the viscosity was found to be greater prior to stopping treatment at low shear rates and greater after stopping treatment at high shear rates. In a second patient no significant change was observed in viscosity. Future study should investigate the effect of glucosamine on viscoelastic behaviour, and to study the effect of glucosamine on synovial fluid viscosity over an extended period of time. A PDMS microfluidic rheometer was developed using a soft-lithography process. The rheometer was validated with water at room temperature and was found to predict fluid viscosity with a maximum of 6% error at shear rates as high as 30,000 s-¹. It is recommended to investigate possible channel deformation as a cause for decreased accuracy at higher shear rates and resultant operating pressures.Applied Science, Faculty ofGraduat