Objective: To investigate the pathological characteristics of subchondral bone and articular cartilage in different animal models of osteoarthritis (OA).
Methods: Using three SD rat osteoarthritis models, 24 6-month-old female rats were randomly divided into 4 groups: sham operation control group (Sham, n=6), anterior cruciate ligament resection group (ACLT, n =6), the papain injection group (Papain, n=6), and the ovariectomized group (OVX, n=6). Knee joints were taken 8 weeks after modeling, and the tibial plateau was analyzed by Micro-CT scan. Cartilage was stained with toluidine blue and Mankin score to compare the changes of subchondral bone and articular cartilage.
Results: 8 weeks after the modeling operation, the degree of cartilage destruction in different OA models was different. The cartilage destruction in ACLT and Papain groups was more severe, while the cartilage changes in the OVX group were mild. The subchondral cancellous bone in all OA models changed, OVX Compared with the Sham control group, the subchondral bone microstructure was significantly loosened in the ACLT group and Papain group, compared with the Sham control group, the subchondral bone microstructure did not change significantly, but compared with the OVX group, there were significant differences. Three types of OA The thickness of the subchondral bone plate of the model is less than that of the Sham group.
Conclusion: The subchondral bone and articular cartilage of the three animal models have obvious pathological changes, and the changes are different. Different OA models represent different pathologies, indicating that the role of subchondral bone is different. This is for further study of different types The mechanism of the occurrence and development of OA, and the use of subchondral bone as a possible target for OA treatment provide more evidence.