This paper presents a comprehensive numerical study of transient non-Newtonian elastohydrodynamic
lubrication of metal-on-metal hip prosthesis subjected to two different gait cycles. The shear-thinning
property of the synovial fluid was found to have a significant effect on the lubricating film, in terms of both
the magnitude and location of the minimum film thickness, and more generally the film thickness
distribution. A range of clearances between the acetabular cup and femoral head were investigated and the
shear-thinning effect was more pronounced in the hip replacements with smaller clearances.