title: Investigations of micron and submicron wear features of diseased human cartilage surfaces.
abstract: Osteoarthritis is a common disease. However, its causes and morphological features of diseased cartilage surfaces are not well understood. The purposes of this research were (a) to develop quantitative surface characterization techniques to study human cartilages at a micron and submicron scale and (b) to investigate distinctive changes in the surface morphologies and biomechanical properties of the cartilages in different osteoarthritis grades. Diseased cartilage samples collected from osteoarthritis patients were prepared for image acquisition using two different techniques, that is, laser scanning microscopy at a micrometer scale and atomic force microscopy at a nanometer scale. Three-dimensional, digital images of human cartilages were processed and analyzed quantitatively. This study has demonstrated that high-quality three-dimensional images of human cartilage surfaces could be obtained in a hydrated condition using laser scanning microscopy and atomic force microscopy. Based on the numerical data extracted from improved image quality and quantity, it has been found that osteoarthritis evolution can be identified by specific surface features at the micrometer scale, and these features are amplitude and functional property related. At the submicron level, the spatial features of the surfaces were revealed to differ between early and advanced osteoarthritis grades. The effective indentation moduli of human cartilages effectively revealed the cartilage deterioration. The imaging acquisition and numerical analysis methods established allow quantitative studies of distinctive changes in cartilage surface characteristics and better understanding of the cartilage degradation process.
authors.affiliation: School of Mechanical and Manufacturing Engineering, The University of New South Wales, Sydney, NSW, Australia.
authors.forename: Zhongxiao
authors.initials: Z
authors.lastname: Peng
authors.affiliation: School of Mechanical and Manufacturing Engineering, The University of New South Wales, Sydney, NSW, Australia juancarlos.baena@gmail.com.
authors.forename: Juan C
authors.initials: JC
authors.lastname: Baena
authors.affiliation: School of Mechanical and Manufacturing Engineering, The University of New South Wales, Sydney, NSW, Australia College of Mechanical and Electrical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China.
authors.forename: Meiling
authors.initials: M
authors.lastname: Wang
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002358:Cartilage, Articular / Q000473:pathology* / Q000648:ultrastructure*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D018625:Microscopy, Atomic Force; D008875:Middle Aged; D010003:Osteoarthritis / Q000473:pathology*; D013499:Surface Properties
keywords: Wear features; effective indentation modulus; image acquisition in three dimensions; numerical characterizations; osteoarthritis; surface morphology