In this paper general classification of the lubrication regimes in synovial hip joint was given The
discussion was focused on two main points, the calculation of film thickness and minimum film
thickness for each of the (hydrodynamic lubrication, squeeze film lubrication and, elastohydrodynamic lubrication), and the relationship between film thickness and gait cycle (stance phase
and swing phase) also and the coefficient friction. Physical properties affecting the film thickness for
different types lubrication will be discussed in each lubrication system.