Effects of Cartilage Constitutive Model on Specimen-Specific Validation and Predictions of Cartilage Mechanics in the Human Hip

The initiation and progression of hip osteoarthritis (OA) may be predicted by mechanical factors [1]. Contact stress (CS), maximum shear stress (MSS) at the osteochondral interface and first principal strain (FPS) at the articular surface have been identified as parameters that alter the physical integrity and metabolism of cartilage [1]. Although these parameters are difficult to measure in-vivo, they can be predicted using finite element (FE) models. However, the reliability of model predictions and the effects of model assumptions are largely unknown. Direct validation of FE models against experimental measurements for a series of specimens shows the reliability of predictions across specimen geometry [1], although to date this has only been performed for a single hip [2].