Short notes on Haversian system

Within the matrix of the bone are found a number of layers called lamel­lae. These are arranged in concentric rings around narrow longitudinal cavities called Haversian canals. The Lamellae that surround the haver­sian canals are called haversian lamellae. Some lamellae however are arranged concentrically around the marrow cavity.

These are called cir­cumferential lamellae. Within the lamellae are found small fluid spaces called bone lacunae. These give off fine radiating canals called canali­culi. Each lacuna has a bone cell or an osteocyte. The canaliculi help in communication between different bone cells.

Small protoplasmic strands extend from the bone cells and form a network throughout the matrix. The Haversian canal together with lamellae, lacunae and canaliculi forms a Haversian system.