Parametric analysis of the stress distribution on the articular cartilage and subchondral bone.

Few studies have stressed on the sensitivity of stress distribution in different mechanical properties of the articular cartilage and subchondral bone. The purpose of this study was to establish parametric variations of mechanical factors individually and examine how these biomechanical effects influenced the cartilage and subchondral bone plate stress fields in the hip joint. A finite element model including acetabulum and proximal femur was established to study the stress change associated with the thinning of cartilage, the increasing of subchondral bone modulus and the thickening of subchondral bone plate individually. The stress distributions in bone/cartilage interface were evaluated. Sensitivity of the stress magnitudes to the parametric changes was also analyzed. The results indicated that cartilage thinning has more significant effect than subchondral bone modulus increasing or thickening on the shear stress levels in subchondral bone/cartilage interface. Subchondral bone plate modulus increasing has mild effect on the shear stress in subchondral bone/cartilage interface. Cartilage thinning acts as a major influence on the development of the articular cartilage damage.