title: Damage initiation and progression in the cartilage surface probed by nonlinear optical microscopy.
abstract: With increasing interest in treating osteoarthritis at its earliest stages, it has become important to understand the mechanisms by which the disease progresses across a joint. Here, second harmonic generation (SHG) microscopy, coupled with a two-dimensional spring-mass network model, was used to image and investigate the collagen meshwork architecture at the cartilage surface surrounding osteoarthritic lesions. We found that minor weakening of the collagen meshwork leads to the bundling of fibrils at the surface under normal loading. This bundling appears to be an irreversible step in the degradation process, as the stress concentrations drive the progression of damage, forming larger bundles and cracks that eventually form lesions.
authors.affiliation: Botnar Research Centre, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, United Kingdom. cameron.brown@ndorms.ox.ac.uk
authors.forename: C P
authors.initials: CP
authors.lastname: Brown
authors.forename: M-A
authors.initials: MA
authors.lastname: Houle
authors.forename: M
authors.initials: M
authors.lastname: Chen
authors.forename: A J
authors.initials: AJ
authors.lastname: Price
authors.forename: F
authors.initials: F
authors.lastname: Légaré
authors.forename: H S
authors.initials: HS
authors.lastname: Gill
mesh_terms: D000818:Animals; D002356:Cartilage / Q000378:metabolism* / Q000473:pathology*; D002417:Cattle; D003094:Collagen / Q000378:metabolism; D018450:Disease Progression; D008853:Microscopy / Q000379:methods*; D055620:Optical Phenomena; D010003:Osteoarthritis / Q000378:metabolism* / Q000473:pathology*; D013499:Surface Properties
chemical_list: D003094:Collagen