Page 273 - Atlas of Histology with Functional Correlations

(4, 12). A synovial membrane, together with the connective tissue, may extend

into the joint cavity as synovial folds (2, 13). The synovial cavity (3) is covered
by a connective tissue capsule.

In the lower bone, an active epiphyseal plate (16) is seen between the
secondary ossification center (5) and the developing shaft of the bone. A zone of
proliferating chondrocytes (7) and a zone of chondrocyte hypertrophy and

calcification of cartilage (8) are visible in the epiphyseal plate (16). Small
spicules of calcified cartilage (9, 15) surrounded by red-stained bony material
and primitive bone marrow cavities with hematopoiesis (14, 17) are seen in
the shaft of the bone and the secondary center of ossification (5). A

megakaryocyte (18) is also visible in the lower bone marrow cavity (17).
Periosteum (19) surrounds the compact bone (10).

FIGURE 7.22 ■ Endochondral ossification: formation of secondary (epiphyseal)
centers of ossification and the epiphyseal plate in a long bone (decalcified bone,

longitudinal section). Stain: hematoxylin and eosin. Low magnification.

FIGURE 7.23 | Bone Formation: Development of

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