title: X-ray diffraction of the molecular substructure of human articular cartilage.
abstract: The molecular substructure of human articular cartilage has been difficult to study because of its complex composition and high degree of hydration. Using newly available small-angle X-ray diffraction (SAX) instrumentation that allows very short exposure times (0.1 to 10 sec), we have obtained spatially resolved information concerning the disposition of collagen fibers in the matrix of cartilage from the normal and osteoarthritic ankle and knee joints of human cadavers. Surprisingly, in zones of cartilage damage, such as in preosteoarthritic lesions or in the severely degenerated cartilage of osteoarthritic joints, collagen fibers of the deeper layers tended to be reoriented from the vertical. The SAX technique represents a nondestructive method of analyzing the collagen network in cartilage. Taken together, the data suggest a rigid control mechanism for the fiber network and an extensive passive reorganization of the collagen fiber orientation in diseased joint cartilage.
authors.affiliation: Department of Orthopedic Surgery, University of Jena, Eisenberg, Germany.
authors.forename: Juergen
authors.initials: J
authors.lastname: Mollenhauer
authors.forename: Matthias
authors.initials: M
authors.lastname: Aurich
authors.forename: Carol
authors.initials: C
authors.lastname: Muehleman
authors.forename: Giorgi
authors.initials: G
authors.lastname: Khelashvilli
authors.forename: T C
authors.initials: TC
authors.lastname: Irving
mesh_terms: D000843:Ankle Joint / Q000000981:diagnostic imaging; D002358:Cartilage, Articular / Q000000981:diagnostic imaging*; D003094:Collagen / Q000032:analysis; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging; D015394:Molecular Structure; D020370:Osteoarthritis, Knee / Q000000981:diagnostic imaging; D011859:Radiography; D014961:X-Ray Diffraction / Q000379:methods*
chemical_list: D003094:Collagen