Epiphyseal Growth Plate (Physis)
Definition
The cartilaginous zone between the epiphysis and metaphysis where endochondral ossification occurs during growth. Closes (fuses) at puberty under the influence of sex steroids. The degree of fusion in specific epiphyses provides the primary biological-age anchor for sub-adult skeletal individuals.
- Location
- Between the epiphysis and metaphysis
- Process
- Endochondral ossification
- Closure trigger
- Sex steroids at puberty
- Forensic use
- Primary age anchor for sub-adult skeletal remains
Common questions
Why do different epiphyses give different weight to a sub-adult age estimate?+
Individual growth plates fuse in a documented sequence and age range across the skeleton, so an examiner scores fusion status across multiple sites rather than relying on one, since some sites fuse early and others fuse late into the twenties.
Does growth plate fusion status work for adult age estimation too?+
No, once all major plates have fused the method loses its resolving power, so adult age estimation switches to other indicators, such as pubic symphysis morphology or histological bone changes.
Related terms
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- Wolff's Law
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