Journal Article
Elastic, Viscoelastic and Fibril-Reinforced Poroelastic Material Properties of Healthy and Osteoarthritic Human Tibial Cartilage
Mohammadhossein Ebrahimi; Simo Ojanen; Ali Mohammadi; Mikko A. Finnilä; Antti Joukainen; Heikki Kröger; Simo Saarakkala; Rami K. Korhonen; Petri Tanska
Annals of Biomedical Engineering · Vol. 47, Issue 4 · pp. 953-966 · 2019
Abstract
Articular cartilage constituents (collagen, proteoglycans, fluid) are significantly altered during osteoarthritis (OA). A fibril-reinforced poroelastic (FRPE) material model can separate the contribution of each constituent on the mechanical response of cartilage. Yet, these properties and their OA related alterations are not known for human tibial cartilage. To answer this gap in the knowledge, we characterized the FRPE as well as elastic and viscoelastic properties of healthy and osteoarthritic human tibial cartilage. Tibial osteochondral explants ( n = 27) harvested from 7 cadavers were mechanically tested in indentation followed by a quantification of elastic, viscoelastic and FRPE properties. Then they were histopathologically OARSI graded for the severity of OA. FRPE modeling revealed that non-fibrillar matrix modulus was higher in the healthy group compared to the early OA ( p = 0.003) and advanced OA ( p healthy group compared to the early OA ( p = 0.009) and advanced OA ( p p = 0.002, r = 0.56). For the first time, the FRPE properties were characterized for human tibial cartilage. This knowledge is crucial to improve the accuracy of computational knee joint models.