Black Colouration of the Knee Articular Cartilage after Spontaneously Recurrent Haemarthrosis

Figure 3

Histological findings. (a) In the lateral femoral condyle bone, safranin O staining of the cartilage lesion is reduced at the transitional and radial zones. (b) Berlin blue staining reveals hemosiderin deposition (arrowhead) in the superficial articular cartilage, and (c) lipofuscin (brown granules that are indicated by the arrows) deposition is also visible in the superficial articular cartilage via Fontana Masson staining.

(a)

(b)

(c)