Parametric numerical analysis for micro-movements investigation at taper junction in total hip arthroplasty

Over the next 40 years, because of the average age rising of the patients and decrease of the age at which arthroplasty is carried out, the demand of orthopaedic implants is expected to grow. In particular, a 673% increase of primary THA is expected and a remarkable increase of revision surgery (+137%) has been estimated as well. Although the continuous developments in implants design and manufacturing, further improvements are strongly required to delay secondary surgeries that imply stress and risk for patients as well as important spending for National Health Cares. Implants failure and consequent revision are generally triggered by wear, corrosion, and oxidation phenomena. In particular, during in vivo operating life, taper junctions between implant components undergo cyclic micro-movements which ultimately leads to a fretting-corrosion process generating cytotoxic metal debris and ions. In this work, biomechanical analysis, combining multibody (MB) and finite element (FE) simulations, were carried out to estimate the range of micro-movements at the headneck taper junction of a parametrized hip prosthesis.