Page 262 - Atlas of Histology with Functional Correlations

FIGURE 7.18 ■ Histology of a section of formed compact bone.

In compact bone, the collagen fibers are arranged in thin layers of bone called

lamellae that are parallel to each other in the periphery or concentrically
arranged around the blood vessels. In a long bone, the outer circumferential
lamellae are deep to the surrounding connective tissue periosteum. Inner

circumferential lamellae are located around the bone marrow cavity.
Concentric lamellae surround the canals that contain an artery, vein, nerve, and
loose connective tissue. Each concentric lamellar complex is called the osteon
(Haversian system). The space in the osteon that contains blood vessels and
nerves is the central (Haversian) canal. Most of the compact bone consists of

osteons, which are usually oriented along the long axis of the bone (see Fig.
7.18).

BONE TYPES

Distribution and orientation of the collagen fibers in the bone matrix indicate the
bone type. The compact and cancellous adult bones exhibit a consistent

structural pattern after maturation and mineralization. In contrast, woven
(immature or primary) bone shows a random arrangement of collagen fibers;

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