The use of larger femoral heads in Total Hip Arthroplasty has increased in order to reduce the risk of dislocation and to improve the range of motion of the joint. In 2003, within the UK, the “standard” head size of 28mm was used in 73% of all hip procedures, whereas by 2012, this figure dropped to 36%. Concerns regarding the impact of this increment in head size on the cement and bone stresses have arisen; however, this has yet to be clearly determined. To understand the relationship between femoral head size and cement mantle and bone stress in cemented hip arthroplasty, 3D-Finite-Element models of a hemipelvis with cemented cup[tb6] (50mm outer-diameter) were developed. Loading conditions of single-leg-stance (average and overweight) were simulated for three head sizes (28, 32 and 36mm). The models were validated with an in-vitro experiment using the average loading condition.Introduction
Methods
