Fig. 2

Representative DCR-images (original size and 3× magnification as shown in red boxes) of the cartilage-bone specimens taken from the distal tibia and talus of three donors with different OA grades (i.e. OARSI = 0, OARSI < 3 and OARSI ≥3). The corresponding histological images of the distal tibial and talar cartilage are presented. Safranin-O staining was used to evaluate the histological OA grade of the hyaline cartilage. Calcification was histochemically confirmed using von Kossa staining