Wormian Bones
Definition
Accessory ossicles (Inca bones) within cranial sutures, particularly the lambdoid; their presence interrupts suture scoring and must be noted before applying Meindl-Lovejoy composite sums to affected sites.
- Also called
- Inca bones
- Location
- Cranial sutures, particularly lambdoid
- Type
- Accessory ossicles
- Effect on ageing method
- Interrupts suture scoring for Meindl-Lovejoy composite sums
Common questions
Why do Wormian bones cause a problem for cranial suture age estimation?+
The Meindl-Lovejoy method scores fusion along a continuous suture line, and an accessory ossicle breaks that continuity at the site it occupies, so the examiner must note and exclude or adjust for affected segments rather than scoring them as if the suture were unbroken.
Are Wormian bones themselves useful for anything beyond flagging a scoring exclusion?+
Their number and location can occasionally support population or individual variation studies, but in routine age-at-death casework their main practical role is as a marker the examiner must recognise so it does not distort the suture-based age estimate.
Related terms
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- Ectocranial Scoring
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- Iscan-Loth Method
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- Meindl-Lovejoy Vault System
- A five-site composite scoring system for ectocranial suture closure at midlambdoid, lambda, obelion, anterior sagittal, and bregma sites, derived from the Hamann-Todd...
- Over-50 Ceiling
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- Skeletal Histomorphometry
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