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.