Static, dynamic, and fatigue life investigation of a hip prosthesis for walking gait using finite element analysis

ABSTRACT Total hip arthroplasty (THA) is a common procedure that is performed for elderly people who suffer from hip pain and other hip-related problems. THA is an operation where an artificial joint is implanted in the femur and acts as the hip joint. THA has seen advancement to a greater extent in the 20th century. In this work, a novel hip implant design is proposed based on the existing literature data. The hip implants were provided with radial clearance between the head and stem junction. This implant design is analyzed by applying a walking gait that has been clinically prerecorded. Linear and volumetric wear rates are estimated at the head-stem junction, head-liner, and liner to acetabulum using Archard’s wear law. Total deformation, von Mises stress, contact stress, linear and volumetric wear rates were reported. The volumetric wear rate was found to be less than the existing literature, achieving the goal of increasing the life expectancy of the total hip prosthesis. The maximum wear rate is found at the head-stem junction for press-fit. It is observed that when the acetabular cup and femoral head are made of CoCr (Cobalt-Chromium) alloy, the liner with Ultra high molecular weight polyethylene (UHMWPE) and the stem with titanium alloy have a lesser wear rate when compared to other material combinations. Further, it is also found that the fatigue life of Ti (Titanium) alloy is higher than that of CoCr alloy and Ti alloy material combinations have the maximum factor of safety.