Pre-clinical analysis of an acetabular cup with improved in-vivo stability and integrity

A finite element analysis study was conducted to produce a ceramic bearing modular acetabular cup prosthesis design with reduced wall thickness, allowing a larger diameter bearing to be used reducing dislocation risk but without compromising bone conservation. In addition to geometric design, pre-assembly of the modular components was considered, so that the integrity of the cup in-vivo would be maintained, potentially reducing fracture risk and the incidence of squeaking. The result was a design with 4mm larger bearing diameter but 20% lower peak ceramic stress than current technology, and an assembly technique predicted to maintain implant integrity in the presence of dimensional variation from manufacturing. Such a design would represent an improvement in stability and integrity in-vivo over current technology, and a necessary improvement in prosthesis design.