Calcium content analysis of articular cartilage in normal and experimental OA model following long term usage of Dex. (A) Representative images of scanning electron microscopy of articular cartilage with or without Dex. (B) Calcium content in each layer of articular cartilage (non-calcified cartilage layer: AC, calcified cartilage layer: CC, subchondral bone plate: SBP) was determined by energy dispersive spectrometer analysis at 4 and 12 weeks compared with control group with intraperitoneal injection of Dex (n = 3). (C) Representative images of scanning electron microscopy of articular cartilage at 4, 8 and 12 weeks after DMM surgery with or without Dex. (D) Calcium content in each layer of articular cartilage (non-calcified cartilage layer: AC, calcified cartilage layer: CC, subchondral bone plate: SBP) was determined by energy dispersive spectrometer analysis at 4, 8 and 12 weeks after DMM surgery with or without Dex (n = 3). Scale bar: 50 µm. Comparisons of multiple groups were evaluated using analysis of variance (ANOVA) followed by Tukey's test. Data were expressed as the mean ± SD. *, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001.