Longitudinal histologic analysis of cartilage degradation and subchondral bone sclerosis induced by DMM surgery. (A) Alcian blue/Hematoxylin and Orange G staining of the coronal sections of the knee joints collected at different time points as indicated. Black arrow, cartilage degradation. Green arrow, subchondral bone sclerosis. Scale bar, 50 μm. n = 5. (B) Alcian blue/Hematoxylin Orange G staining of the coronal sections of the joints collected 4 weeks after surgery. Black arrow, cartilage degradation. White arrow, subchondral bone sclerosis in the medial tibiae. Red arrow, subchondral bone loss in the lateral tibiae. L, lateral tibiae; M, medial tibiae. Scale bar, 200 μm. n = 5.