An integral biochemical analysis of the main constituents of articular cartilage, subchondral and trabecular bone  Mark R. van der Harst, D.V.M., Pieter A.J. Brama, Ph.D., Chris H.A. van de Lest, Ph.D., Geesje H. Kiers, Jeroen DeGroot, Ph.D., P.René van Weeren, Ph.D.  Osteoarthritis and Cartilage  Volume 12, Issue 9, Pages 752-761 (September 2004) DOI: 10.1016/j.joca.2004.05.004

Fig. 1 Sample sites on the proximal articular surface of the first phalanx (1=mediodorsal articular margin; 2=central fovea). Osteoarthritis and Cartilage 2004 12, 752-761DOI: (10.1016/j.joca.2004.05.004)

Fig. 2 Percentage denatured collagen (mean±SD) in cartilage, subchondral- and trabecular bone at the joint margin, site 1 (solid bars) and the central fovea, site 2 (open bars) of the proximal first phalanx. Asterisks denote significant difference between the two different sites and subchondral bone vs trabecular bone; *P<0.05, **P<0.01, ***P<0.001. Osteoarthritis and Cartilage 2004 12, 752-761DOI: (10.1016/j.joca.2004.05.004)

Fig. 3 Hydroxylysine content (mol/triple helix; mean±SD) of cartilage, subchondral- and trabecular bone at the joint margin, site 1 (solid bars) and the central fovea, site 2 (open bars) of the proximal first phalanx. Hyl=hydroxylysine. For further explanation see caption of Fig. 2. Osteoarthritis and Cartilage 2004 12, 752-761DOI: (10.1016/j.joca.2004.05.004)

Fig. 4 Hydroxylysylpyridinoline cross-linking (mol/mol triple helix collagen; mean±SD) of cartilage, subchondral- and trabecular bone at the joint margin, site 1 (solid bars) and the central fovea, site 2 (open bars) of the proximal first phalanx. HP=hydroxylysylpyridinoline. For further explanation see caption of Fig. 2. Osteoarthritis and Cartilage 2004 12, 752-761DOI: (10.1016/j.joca.2004.05.004)

Fig. 5 (a) Number of pentosidine cross-links (mmol/mol triple helix collagen) in equine cartilage in relation to age at the joint margin, site 1 and the central fovea, site 2 of the first phalanx. P=significance level; r=correlation coefficient. (b) Number of pentosidine cross-links (mmol/mol triple helix collagen) in subchondral bone in relation to age at the central fovea, site 2 of the first phalanx. P=significance level; r=correlation coefficient. (c) Number of pentosidine cross-links (mmol/mol triple helix collagen) in equine trabecular bone in relation to age at the joint margin, site 1 and the central fovea, site 2 of the first phalanx. P=significance level; r=correlation coefficient. Osteoarthritis and Cartilage 2004 12, 752-761DOI: (10.1016/j.joca.2004.05.004)

Fig. 6 (a) Correlation between calcium content (mmol/g dw) and total amount of pyridinoline cross-links (HP plus LP in mol/mol triple helix) at the joint margin, site 1 and the central fovea, site 2 of subchondral bone samples of the proximal first phalanx. HP=hydroxylysylpyridinoline; LP=lysylpyridinoline; dw=dry weight; P=significance level; r=correlation coefficient. (b) Correlation between calcium content (mmol/g dw) and total amount of pyridinoline cross-links (HP plus LP in mol/mol triple helix) at the joint margin, site 1 and the central fovea, site 2 of trabecular bone samples of the proximal first phalanx. HP=hydroxylysylpyridinoline; LP=lysylpyridinoline; dw=dry weight; P=significance level; r=correlation coefficient. Osteoarthritis and Cartilage 2004 12, 752-761DOI: (10.1016/j.joca.2004.05.004)

Fig. 7 BMD (mg/cm3; mean±SD) measured 2mm under the cartilage layer through the subchondral bone plate and at a depth of 8mm through the trabecular bone at the joint margin, site 1 (solid bars) and the central fovea, site 2 (open bars) of the first phalanx. BMD=bone mineral density. For further explanation see caption of Fig. 2. Osteoarthritis and Cartilage 2004 12, 752-761DOI: (10.1016/j.joca.2004.05.004)