Secondary Osteon
Definition
A remodelling unit in cortical bone visible in cross-section as a concentric ring structure (Haversian system). Osteon diameter and density are size-correlated and provide a gross indicator of body mass when species identity is unknown.
- Also called
- Haversian system
- Appearance
- Concentric lamellar rings in cross-section
- Formed by
- Bone remodelling replacing primary bone
- Forensic use
- Size and density estimate body mass
Common questions
How does a secondary osteon differ from primary bone tissue microscopically?+
Primary bone is laid down directly during initial growth without a resorption line, while a secondary osteon forms when remodelling removes existing bone and refills the space with concentric lamellae bounded by a visible cement line.
Why is osteon size used to estimate body mass when species is uncertain?+
Haversian canal and osteon dimensions scale broadly with body size across mammals, so gross histomorphometric measurement can support a rough mass estimate for fragmentary bone of unknown origin, such as suspected wildlife product.
What limits osteon-based estimates in wildlife forensic cases?+
Remodelling rate and osteon geometry vary with age, bone type, mechanical loading, and taxon, so histological estimates are usually treated as corroborating evidence alongside DNA or other species-identification methods.
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