A New Criterion for the Human Knee Osteoarthritis Characterization: Finite Element modelling

Osteoarthritis (OA), characterized by the degradation of articular cartilage, is a musculoskeletal disease that occurs as the result of variations in the mechanical stress and strain applied to the knee joint. Since damaged cartilage has very poor intrinsic repair and regenerative capacity, numerical modeling complemented by experimental studies have been widely investigated to examine the causes of OA development. However, the responses of the articular cartilage to a load distributed as a function of knee laxity in the frontal plane have not been studied numerically. Accordingly, we provide in this paper a 3D finite element (FE) model of the knee joint obtained from Magnetic Resonance Imaging (MRI) dataset, in order to assess the biomechanical responses of cartilage. The main goal of this work is to develop a new methodology to quantify the load applied to the knee and to propose a new criterion for characterizing cartilage wear based on arthroscopic and radiological classifications. In the situations of varus and valgus laxity, the FE analysis demonstrated that degenerative cartilage degradation is seen to be larger for higher abnormalities. Moreover, numerical modeling of the new criterion allowed for the identification of OA phases based on the rate of cartilage wear measured for the various FE knee models.