Analysis of friction of hip joint replacements with modification of surface topography

Hip endoprosthesis introduces an effective treatment for patients suffering from advanced stages of hip degeneration. Despite the advancements made in recent years, limited longevity negatively affects the application of this technology in young patients. The main mechanism which causes limited longevity is wear, which depends on the friction and lubrication of the joint. This thesis aims to observe the effect of a textured surface on a UHMWPE polyethylene cup combined with a smooth femoral head as a solution, which may reduce the friction and wear of the contact surfaces. Two textured cups and three smooth femoral heads were used in the experiment (ceramic, metal, oxinium). The results showed that the textured surface has a positive effect on both reducing friction and providing more stability with the use of synovial fluid. A significant reduction in friction is observed for the surface with smaller dimples rather than for the surface with larger ones. Specifically, the combination of a ceramic femoral head and a finely dimpled surface resulted in the reduction of friction by 66 %. Attention was also paid to the effect of the load on the hip. In most cases, the load did not significantly impact the results. It can be assumed that reducing the friction at the joint leads to the reduction of the rate of wear, thus increasing the implant longevity