Haversian System
http://webs.ashlandctc.org/mflath/KEY%20SKELETAL%20I%20OBJECTIVES.htm
Clopton Harvers
Born in 1655 in England Studied at Cambridge Both a Physician and an Anatomist Practiced medicine in London for most of his
life Credited for his in-depth studies of the bones
that ultimately led to the discovery of the 'Haversian canals' in them
Died in 1702
What exactly is a Harversian System? Compact bone contains many cylinder-shaped
structural units called osteons (Haversian systems) Each osteon runs lengthwise through the bone These Haversian systems makeup the structural
framework of compact bone The unique composition of the osteons allows for
the delivery of nutrients and the removal of certain waste products produced from metabolically active bone cells
Composition of the Haversian System Four types of structures make up each
osteon (haversian system) 1. Lamellae 2. Lacunae 3. Canaliculi 4. Haversian Canal
Lamellae (la-MEL-ay)
Concentric, cylinder-shaped layers of calcified matrix
http://faculty.une.edu/com/abell/histo/Histolab4e.htm
Lacunae (la-KYOO-nay)
Latin for “little lakes” Small spaces containing tissue fluid in which
bone cells lie imprisoned between the hard layers of the lamellae
http://faculty.une.edu/com/abell/histo/Histolab4e.htm
Canaliculi (CAN-uh-LIK-you-lye) Very tiny canals radiating in all directions
from the lacunae and connecting them to each other and into the Haversian canal
http://faculty.une.edu/com/abell/histo/Histolab4e.htm
Haversian Canal
Extends lengthwise through the center of each osteon Contains blood vessels, lymphatic vessels, and nerves from the
Haversian canal Nutrients and oxygen move through canalculi to the lacunae and
their bone cells Each Haversian canal is connected by tansverse Volkmann’s canals
(contain nerves and vessels that carry blood and lymph to the osteons)
http://newscenter.lbl.gov/feature-stories/2008/08/06/the-toughness-of-bone/