Search results
Results from the WOW.Com Content Network
The channels are formed by concentric layers called lamellae, which are approximately 50 μm in diameter. The Haversian canals surround blood vessels and nerve cells throughout bones and communicate with osteocytes (contained in spaces within the dense bone matrix called lacunae) through connections called canaliculi.
Each osteon consists of concentric layers, or lamellae, of compact bone tissue that surround a central canal, the Haversian canal. The Haversian canal contains the bone's blood supplies. The boundary of an osteon is the cement line. Each Haversian canal is surrounded by varying number (5-20) of concentrically arranged lamellae of bone matrix.
It consists of multiple microscopic columns, each called an osteon or Haversian system. Each column is multiple layers of osteoblasts and osteocytes around a central canal called the osteonic canal. Volkmann's canals at right angles connect the osteons together. The columns are metabolically active, and as bone is reabsorbed and created the ...
Within the bone itself, the haversian canals become blocked with scar tissue, and the bone becomes surrounded by thickened periosteum. [ citation needed ] Due to the avascular nature of this bone, antibiotics which travel to sites of infection via the bloodstream poorly penetrate these tissues, hence the difficulty in treating chronic ...
Bone canaliculi are microscopic canals between the lacunae of ossified bone. The radiating processes of the osteocytes (called filopodia) project into these canals. These cytoplasmic processes are joined together by gap junctions. Osteocytes do not entirely fill up the canaliculi.
Volkmann's canals, also known as perforating holes or channels, are anatomic arrangements in cortical bones that allow blood vessels to enter the bones from periosteum. They interconnect the Haversian canals (running inside osteons ) with each other and the periosteum.
Havers' thesis. Clopton Havers (24 February 1657 – April 1702) was an English physician who did pioneering research on the microstructure of bone. He is believed to have been the first person to observe and almost certainly the first to describe what are now called Haversian canals and Sharpey's fibres.
Ossification is started by the formation of layers of undifferentiated connective tissue that hold the area where the flat bone is to come. On a baby, those spots are known as fontanelles. The fontanelles contain connective tissue stem cells, which form into osteoblasts, which secrete calcium phosphate into a matrix of canals. They form a ring ...