Figure 4

Scanning electron microscopy of morphological aspects of calcium-containing crystals in osteoarthritic knee articular cartilage. Representative images of crystals in cartilage. (A) Cartilage without calcification. (×755 magnification). (B) Agglomeration of several apatite crystallites localized in structure sets suggestive of chondrons and an agglomeration of apatite crystallites (×755 magnification). (C) Typical rod-shaped calcium pyrophosphate crystals and cubic morphologic feature of some crystallites (×2,999 magnification).