Computational prediction of remodeling of collagen fiber network in articular cartilage under dynamic unconfined compression

A poroelastic finite element model of a heterogeneous cartilage disk was created based on previous studies and experimental setups; this allows us to study cartilage behavior under dynamic unconfined compression. Previous studies have used a Post Hoc approach, which consist of searching for patterns or relationships between predicted mechanical parameters obtained through computational and experimental results. Our goal in this study is to take the same Post-Hoc approach and identify patterns between predicted mechanical parameters, such as fiber strain or stress, and experimentally-measured collagen fiber distribution (i.e. reorientation of fibers under dynamic unconfined compression). After computational predictions were obtained, it was observed that stress and pore pressure, in addition to fiber strain, are key to triggering the reorientation of collagen fibers in the cartilage tissue.