Citation

Farr JN, Amin S, LeBrasseur NK, Atkinson EJ, Achenbach SJ, McCready LK, Joseph Melton L, Khosla S. J. Clin. Endocrinol. Metab. 2014; 99(12): 4641-4648.

Affiliation

Division of Endocrinology, Department of Medicine;

Copyright

(Copyright © 2014, Endocrine Society)

DOI

10.1210/jc.2014-1113

PMID

25243571

Abstract

Context: Numerous studies have examined the association of body composition with bone development in children and adolescents, but none have used micro-finite element (μ FE) analysis of high-resolution peripheral quantitative computed tomography (HRpQCT) images to assess bone strength.

OBJECTIVE: To examine the relations of appendicular lean mass (ALM) and total body fat mass (TBFM) to bone strength (failure load) at the distal radius and tibia. Design, Participants, and Setting: Cross-sectional study of 198 healthy 8- to <15-year old boys (n = 109) and girls (n = 89) performed in a Clinical Research Unit.

RESULTS: After adjusting for bone age, height, fracture history, ALM and TBFM, multiple linear regression analyses in boys and girls, separately, showed robust positive associations between ALM and failure loads at both the distal radius (boys: β = 0.92, P<0.001; girls: β = 0.66, P=0.001) and tibia (boys: β = 0.96, P<0.001; girls: β = 0.66, P<0.001). By contrast, in both boys and girls the relationship between TBFM and failure load at the distal radius was virtually nonexistent (boys: β = -0.07; P=0.284; girls: β= -0.03; P=0.729). At the distal tibia, positive, albeit weak, associations were observed between TBFM and failure load in both boys (β = 0.09, P=0.075) and girls (β = 0.17, P=0.033).

CONCLUSIONS: Our data highlight the importance of lean mass for optimizing bone strength during growth, and suggest that fat mass may have differential relations to bone strength at weight-bearing versus non-weight-bearing sites in children and adolescents. These observations suggest that the strength of the distal radius does not commensurately increase with excess gains in adiposity during growth, which may result in a mismatch between bone strength and the load experienced by the distal forearm during a fall. These findings may explain, in part, why obese children are over-represented among distal forearm fracture cases.

Language: en