Periprosthetic bone remodeling. A finite elementstudy of the influence of the implant design

Remodeling periprosthetic femoral bone after total hip arthroplasty has been studied extensively. Finite element (FE) analysis, together with mathematical remodeling theories, has predicted that femoral bone-mineral density decreases proximally after total hip arthroplasty. There is significant controversy concerning the clinical consequences of bone remodeling such as the reduction in bone strength, the possibility of a cement mantle fracture, the aseptic loosening of the implant, or the appearance of a periprosthetic fracture, which could threaten the survival of the hip prosthesis. The status of periprosthetic bone stock is an important concern when total hip arthroplasty revision is undertaken. This study was conducted to evaluate the periprosthetic bone-mineral density evolution following primary total hip arthroplasty by FE analysis. We compared two cemented stems with different designs: the Exeter and the SHP to study the phenomenon of femoral stress shielding and bone cement deterioration. We found that with the best mechanical conditions and with the same materials, the prosthesis design determines a different periprosthetic bone remodeling.