Related Experiment Video
Updated: Apr 1, 2026

Scanning Skeletal Remains for Bone Mineral Density in Forensic Contexts
Published on: January 29, 2018
The effect of loading and ethnicity on annual changes in cortical bone of the radius and tibia in pre-pubertal
Rebecca M Meiring1, Lisa K Micklesfield2, Joanne A McVeigh1
1a Exercise Laboratory, School of Physiology, Faculty of Health Sciences , University of the Witwatersrand , Johannesburg , South Africa and.
Background:
It is unclear what effect habitual physical activity or ethnicity has on annual changes in bone size and strength in pre-pubertal children.
Aim:
To determine whether the annual relative change in bone size and strength differed between high and low bone loaders and also between black and white pre-pubertal children.
Subjects And Methods:
Peripheral quantitative computed tomography (pQCT) scans of the 65% radius and tibia were completed on 41 black and white children (15 boys, 26 girls) between the ages of 8-11 years, at baseline and 1 year later. Children were categorised into either a high or low bone loading group from a peak bone strain score obtained from a bone-specific physical activity questionnaire. Total area (ToA), cortical area (CoA), cortical density (CoD), strength-strain index (SSI), periosteal circumference (PC), endosteal circumference (EC) and cortical thickness (CT) were assessed.
Results:
There was no difference in annual relative change in radial or tibia bone size and strength between the low and high bone loaders. Black children had a greater annual relative change in CoD (p = 0.03) and SSI (p = 0.05) compared to the white children.
Conclusion:
Children who performed high bone loading activities over a 1-year period had similar bone growth to children who did low bone loading activities over the same period. Rapid maturational growth over this period may have resulted in bone adapting to the strains of habitual physical activity placed on it. Black children may have greater tibial bone strength compared to white children due to a greater annual increase in cortical density.
Related Concept Videos
Changes in the Appendicular Skeleton with Age
Initially, the limb buds consist of a core of mesenchyme covered by a layer of ectoderm. The ectoderm at the end of the limb bud thickens to form a narrow crest called the apical ectodermal ridge. This ridge stimulates the underlying...
Relation between Poisson's ratio, Modulus of Elasticity and Modulus of Rigidity
Bone Disorders
Bone deposition is also affected by the levels of sex hormones like estrogen and testosterone that promote osteoblast activity and bone matrix synthesis. When the level of these hormones decreases due to aging, it causes a reduction in bone deposition. As a result, bone resorption by osteoclasts...
General Case of Eccentric Axial Loading
Consider a member subjected to equal and opposite forces that are applied along a line that does not coincide with the member's neutral axis. In unsymmetrical...
Nature and Nurture
Normal Strain under Axial Loading

