The Histology Guide

Cartilage and Bone: Types of mature bone

Compact Bone

osteon diagram TS

The diagram above shows a transverse view of an osteon (Haversian system) - the basic unit of compact bone.

diagram of haversian canal

The diagram above shows a longitudinal view of an osteon.

Some, mostly older, compact bone is remodelled to form these Haversian systems (or osteons). The osteocytes sit in their lacunae in concentric rings around a central Haversian canal (which runs longitudinally). The osteocytes are arranged in concentric rings of bone matrix called lamellae (little plates), and their processes run in interconnecting canaliculi. The central Haversian canal, and horizontal canals (perforating/Volkmann’s) canals contain blood vessels and nerves from the periosteum.

Cancellous Bone

Cancellous bone has large open spaces (marrow spaces) and plates of bone called trabeculae.

This photograph shows a section through a marrow space within a bone.

Can you identify the bone marrow, trabeculae, osteocytes, and some adipocytes, that are in the bone marrow.