Document Type
Article (Restricted)
Publication Date
1-1-2012
Abstract
Experimental findings indicate that in-situ chondrocytes die readily following impact loading, but remain essentially unaffected at low (non-impact) strain rates. This study was aimed at identifying possible causes for cell death in impact loading by quantifying chondrocyte mechanics when cartilage was subjected to a 5 nominal tissue strain at different strain rates. Multi-scale modelling techniques were used to simulate cartilage tissue and the corresponding chondrocytes residing in the tissue. Chondrocytes were modelled by accounting for the cell membrane, pericellular matrix and pericellular capsule. The results suggest that cell deformations, cell fluid pressures and fluid flow velocity through cells are highest at the highest (impact) strain rate, but they do not reach damaging levels. Tangential strain rates of the cell membrane were highest at the highest strain rate and were observed primarily in superficial tissue cells. Since cell death following impact loading occurs primarily in superficial zone cells, we speculate that cell death in impact loading is caused by the high tangential strain rates in the membrane of superficial zone cells causing membrane rupture and loss of cell content and integrity.
Keywords
Finite element modelling, Impact loading, Chondrocyte mechanics, Cell membrane damage, Osteoarthritis, Cartilage mechano-biology
Divisions
fac_eng
Publication Title
Biomechanics and Modeling in Mechanobiology
Volume
11
Issue
7
Additional Information
Moo, E K Herzog, W Han, S K Abu Osman, N A Pingguan-Murphy, B Federico, S eng Canadian Institutes of Health Research/Canada Research Support, Non-U.S. Gov't Germany 2012/01/12 06:00 Biomech Model Mechanobiol. 2012 Sep;11(7):983-93. Epub 2012 Jan 11.