Fig. 5

Cartilage quality and quantity were determined in samples of untreated (circles) and triamcinolone acetonide–treated (squares) rats with equilibrium partitioning of an ionic contrast agent using micro–computed tomography(EPIC-μCT) a–d The amounts of sulphated glycosaminoglycans (sGAGs) (arbitrary grey values in a and b) and cartilage thickness (in micrometres; c and d) were measured in the medial (a and c) and lateral (b and d) cartilage compartments of the tibial plateau harvested from healthy joints (open boxes) and osteoarthritis (OA)-induced joints (grey boxes). Attenuation values from EPIC-μCT scans are inversely related to the sGAG content, meaning that a high attenuation corresponds to low sGAG content. Coronal images from representative EPIC-μCT scans of the tibial plateau show the amount of cartilage (erosions indicated with inverted triangles and dashed lines) and sGAG content (displayed in colour). *p < 0.05, **p < 0.01, ***p < 0.001. Error bars indicate 95 % confidence intervals