title: Histomorphometric analysis of adult articular calcified cartilage zone.
abstract: The aim of this study was to carry out a histomorphometric analysis of calcified cartilage zone (CCZ) and its interfaces between hyaline cartilage and subchondral bone. The study used 40 donated normal human femoral condyles, from which paraffin-embedded sections were prepared after fixation and decalcification. The histomorphology of the CCZ were qualitatively and quantitatively observed by staining, scanning electron microscopy (SEM) and three-dimensional (3D) reconstruction. The hyaline cartilage and CCZ were stained red with Safranin-O, and the subchondral bone was stained blue with Fast green. CCZ was stained black after von Kossa staining. The hyaline cartilage was interlocked tightly in the manner of "ravine-engomphosis" by the CCZ. The surface roughnesses of tidemark and cement line were 1.14+/-0.04 and 1.99+/-0.38. The maximum, minimum and mean thicknesses of CCZ were 277.12+/-8.6, 9.83+/-6.72 and 104.162+/-0.87 microm, respectively. The cell density of CCZ (51.25+/-21.26 cells/mm(2)) was significantly lower than that of the hyaline cartilage (152.54+/-35.77 cells/mm(2)) (P<0.05). The subchondral bone was anchored tightly in the manner of a "comb-anchor" by the CCZ in our 3D reconstruction model. Thus, we discovered two junctional interfaces of CCZ using different histomorphometric methods. The upper interface of CCZ is a "ravine-engomphosis" shape, while its lower interface is a "comb-anchor" shape.
authors.affiliation: Center for Joint Surgery, Southwest Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Fuyou
authors.initials: F
authors.lastname: Wang
authors.forename: Zhang
authors.initials: Z
authors.lastname: Ying
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Duan
authors.forename: Hongbo
authors.initials: H
authors.lastname: Tan
authors.forename: Bin
authors.initials: B
authors.lastname: Yang
authors.forename: Lin
authors.initials: L
authors.lastname: Guo
authors.forename: Guangxing
authors.initials: G
authors.lastname: Chen
authors.forename: Gang
authors.initials: G
authors.lastname: Dai
authors.forename: Zhe
authors.initials: Z
authors.lastname: Ma
authors.forename: Liu
authors.initials: L
authors.lastname: Yang
mesh_terms: D000328:Adult; D002113:Calcification, Physiologic; D002358:Cartilage, Articular / Q000033:anatomy & histology* / Q000502:physiology / Q000648:ultrastructure; D005260:Female; D005269:Femur / Q000033:anatomy & histology / Q000502:physiology / Q000648:ultrastructure; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D008855:Microscopy, Electron, Scanning; D008875:Middle Aged; D055815:Young Adult