Micro-CT analysis the effects of long-term usage of Dex on subchondral bone after DMM surgery. (A) Micro-CT 3D images of subchondral bone in tibia at 4, 8 and 12 weeks after DMM surgery with or without Dex. (B-D) Results showing relative bone mass density (BMD), measurement in the total subchondral bone of tibia with vehicle and Dex treatment after DMM or sham operation (n = 4), showing that the BMD was decreased of tibia at 12 weeks with or without DMM surgery. (E-G) Results showing relative bone volume fraction (bone volume/total volume, BV/TV), measurement in the total subchondral bone of tibia with vehicle and Dex treatment after DMM or sham operation, showing that the BV/TV was decreased of tibia at 12 weeks with or without DMM surgery (n = 4). Comparisons of multiple groups were evaluated using analysis of variance (ANOVA) followed by Tukey's test. Data were expressed as the mean ± SEM. *, P < 0.05; **, P < 0.01;***, P < 0.001; ****, P < 0.0001.