Computational assessment of the effect of polyethylene wear rate, mantle thickness, and porosity on the mechanical failure of the acetabular cement mantle.

Clinical studies have revealed that aseptic loosening is the dominant cause of failure in total hip arthroplasty, particularly for the acetabular component. For a cemented polyethylene cup, failure is generally accompanied by the formation of fibrous tissue at the cement-bone interface. A variety of reasons for the formation of this tissue have been suggested, including osteolysis and mechanical overload at the cement-bone interface.

Accounting for inclusions and voids allows the prediction of tensile fatigue life of bone cement.

Previous attempts by researchers to predict the fatigue behavior of bone cement have been capable of predicting the location of final failure in complex geometries but incapable of predicting cement fatigue life to the right order of magnitude of loading cycles. This has been attributed to a failure to model the internal defects present in bone cement and their associated stress singularities. In this study, dog-bone-shaped specimens of bone cement were micro-computed-tomography (microCT) scanned to generate computational finite element (FE) models before uniaxial tensile fatigue testing.