Department of Applied Physics, University of Eastern Finland, Kuopio, Finland.
Medical Research Center, Bone and Stem Cell Biology Research Group, University of Oulu and Oulu University Hospital, Oulu, Finland.
J Orthop Res. 2021 Dec;39(12):2556-2567. doi: 10.1002/jor.25009. Epub 2021 Mar 11.
Concurrent osteoarthritic (OA) manifestations in bone and cartilage are poorly known. To shed light on this issue, this study aims to investigate changes in subchondral bone and articular cartilage at two time points after anterior cruciate ligament transection (ACLT) in a rabbit model. 2 (N = 16) and 8 (N = 10) weeks after ACLT, the subchondral bone structure, cartilage thickness, Osteoarthritis Research Society International (OARSI) score, fixed charged density (FCD), and collagen orientation angle were analyzed. OA related changes were evaluated by comparing the ACLT to the contralateral (C-L) and control knees. Already 2 weeks after ACLT, higher trabecular number in the medial femoral condyle and femoral groove, greater OARSI score in the femoral condyles, and thinner trabeculae in the lateral tibial plateau and femoral groove were observed in ACLT compared to C-L knees. Only minor changes of cartilage collagen orientation in the femoral condyles and femoral groove and smaller FCD in the femoral condyles, medial tibial plateau, femoral groove and patella were observed. 8 weeks post-ACLT, the surgical knees had thinner subchondral plate and trabeculae, and smaller trabecular bone volume fraction in most of the knee locations. OARSI score was greater in the femoral condyle and lateral tibial plateau cartilage. FCD loss was progressive only in the femoral condyle, femoral groove, and patellar cartilage, and minor changes of cartilage collagen orientation angle were present in the femoral condyles, femoral groove, and lateral tibial plateau. We conclude that ACLT induces progressive subchondral bone loss, during which proteoglycan loss occurs followed by their partly recovery, as indicated by FCD results.
同时存在于骨和软骨中的骨关节炎（OA）表现尚不清楚。为了阐明这个问题，本研究旨在研究兔模型前交叉韧带切断（ACLT）后两个时间点的软骨下骨和关节软骨的变化。在 ACLT 后 2（N=16）和 8（N=10）周时，分析了软骨下骨结构、软骨厚度、骨关节炎研究协会国际评分（OARSI）、固定电荷密度（FCD）和胶原取向角。通过比较 ACLT 与对侧（C-L）和对照膝关节，评估与 OA 相关的变化。在 ACLT 后 2 周，内侧股骨髁和股骨沟的骨小梁数量增加，股骨髁的 OARSI 评分更高，外侧胫骨平台和股骨沟的骨小梁变薄，与 C-L 膝关节相比，ACLT 膝关节观察到这些变化。仅观察到股骨髁和股骨沟软骨胶原取向的轻微变化和股骨髁、内侧胫骨平台、股骨沟和髌骨的 FCD 较小。ACLT 后 8 周，手术膝关节的软骨下板和小梁变薄，大多数膝关节部位的小梁骨体积分数减小。股骨髁和外侧胫骨平台软骨的 OARSI 评分更大。仅在股骨髁、股骨沟和髌骨软骨中，FCD 丢失呈进行性，且股骨髁、股骨沟和外侧胫骨平台软骨的胶原取向角有轻微变化。我们的结论是，ACLT 导致进行性软骨下骨丢失，在此期间，FCD 结果表明，蛋白聚糖丢失后部分恢复。
