Correlation between subchondral bone mass and cartilage degeneration / 中国组织工程研究

ABSTRACT

BACKGROUND:Correlation between subchondral bone and articular cartilage in the process of osteoarthritis has not been fuly elucidated. Degeneration of cartilage is the focus of attention, and the subchondral bone also plays an important role in the process of osteoarthritis. OBJECTIVE: To observe the differences between experimental osteoarthritis models in rabbit knees established by two kinds of surgical methods and two kinds of proteases inducing methods, and to explore the correlation between subchondral bone mass and degeneration of cartilage. METHODS:Thirty-two New Zealand rabbits were randomly and averagely divided into four groups: Hulth group (group A), anterior cruciate ligament transaction group (group B), colagenase type II group (group C) and papain group (group D). The right knees of rabbits were established as osteoarthritis models, and the left knees served as controls. Bone mineral density of the knee joint was evaluated by dual-energy X-ray absorptiometry scanning at 0, 4 and 8 weeks after modeling. The rabbits were sacrificed at 8 weeks after MRI scanning, bilateral knee joints were harvested for general and histological observation. Quantitative analysis was done according to Mankin scores. RESULTS AND CONCLUSION: Bone mineral density of the right knees decreased at 0, 4 and 8 weeks after modeling, and the rank was as folows: group A > group B > group C > group D. MRI scanning showed that the articular cartilage thickness of the medial and lateral femoral condyle on the right knees became thinner compared with the left side, and the rank was as folows: group A < group B < group C < group D. Observation by specimens and pathological slices showed that the articular cartilage degeneration of the surgery groups worsened, group A was the most serious one, and group 1D was the lightest. Both surgery and proteases inducing methods can successfuly establish osteoarthritis models in rabbit knees. Surgery inducing models resemble the advanced or intermediate stage of osteoarthritis, while the proteases inducing models resemble the early stage of osteoarthritis. Degeneration of the articular cartilage and changes of subchondral bone are related in progressive development.