Osteon (Haversian System)
Definition
The basic structural unit of compact cortical bone: a central Haversian canal surrounded by concentric lamellae of mineralised collagen. Osteon diameter and canal size differ between mammalian orders and can be measured in cross-sections to contribute to taxon identification.
- Location
- Compact cortical bone
- Core structure
- Central Haversian canal, concentric lamellae
- Composition of lamellae
- Mineralised collagen
- Forensic use
- Diameter/canal size aid taxon identification
Common questions
How does osteon size help distinguish human bone from animal bone?+
Osteon and Haversian canal diameters cluster within different ranges across mammalian orders, so measuring cross-sections under a microscope can support distinguishing human fragments from those of common domestic or wild animals when gross morphology is inconclusive.
Can osteon structure also help estimate an individual's age?+
Yes, in histological age estimation the density of intact versus fragmented secondary osteons increases with age due to ongoing bone remodelling, giving one of several inputs used alongside other skeletal indicators.
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Explained in these topics
- Bone and Skeletal Element Identification
- Bone Biology and Forensic SignificanceThe basic structural unit of cortical bone: a central Haversian canal carrying blood vessels, surrounded by concentric layers (lamellae) of mineralised collage...