The total hip replacement is the most commonly performed joint replacement. Although the technology of joint replacement has progressively evolved in the last thirty years, the problem of the long term stability (10 years or more) of hip and knee implants has not been solved. The objective of this research is to evaluate the influence of local bone remodeling at the bone-implant interface on the long term stability and load carrying capacity of the implant. The effect of the interactive temporal evolution of bone remodeling on all surfaces, the bone-implant interface as well as the periosteum and portions of the endosteum that do not contact the implant, on the long term stability of the implant is studied computationally. A set of interchangeable local computational models of contact surface structures that permit the modeling of different interfaces, such as a screw face, a sintered bead or wire mesh face, is developed. The applicability of the model is demonstrated by applying it to basic implant designs seeking conceptual insights into the changing structural behavior of the bone implant system over time due to progressive bone remodeling.

The comparison of the numerical results and clinical observations shows that the models predict many phenomena widely observed in the clinic, such as calcar resorption, cortical bone thickening and so on.

The method of predicting the long term stability of a bone prosthesis will contribute significantly to the improved design of these prostheses and improved surgical placement procedures for implants.