Steroid-associated osteonecrosis animal model in rats

Zheng, Li-Zhen; Wang, Jia-Li; Kong, Ling; Huang, Le; Tian, Li; Pang, Qian-Qian; Wang, Xin-Luan; Qin, Ling

Micro-CTebased trabecular architecture analysis demonstrated significant bone loss at trabecular bone of the proximal tibia 6 weeks after SAON induction, demonstrated by the significant lower BMD, BV/TV, Conn. D., Tb. N and significant higher Tb. Sp in the SAON group. Normally, the Tb. Th becomes thinner during bone loss, while in this ROI, the Tb. Th is relatively higher near the cortical bone and thinner in the middle region. Based on representative micro-CT 3-D images, we could find that the trabeculae in the middle region were almost disappeared in the SAON group; therefore, there was no significant thinner Tb. Th of the SAON group which remained relatively thicker trabeculae near the cortical bone. For the SMI in micro-CT analysis, 0 means ideal parallel plate structure, and 3 means ideal cylindrical rod structure, and the SMI between 0 and 3 is dependent on the volume ratio of rods and plates [37] . In this study, the inner more trabeculae with rod-like structure were almost lost, and the outer more trabeculae with plate-like structure degraded towards more rod-like structure in the SAON group, which explained no significant difference in the SMI between the two groups.