MedWrite Healthcare Communications

Greater lean tissue and skeletal muscle mass in children contributes to higher bone mineral content

In a recent study, the relationship of skeletal muscle mass with bone mineral content was compared in an ethnically diverse group of 6–18 year old boys and girls.

Body mass, height, and Tanner stage were assessed in 175 healthy children (103 boys, 72 girls). Dual-energy X-ray absorptiometry (DXA) was used to assess whole body bone mineral content, non-bone lean body mass, skeletal muscle mass, and fat mass. To estimate muscle mass, an equation using appendicular lean soft tissue measured by DXA, weight and height was used. Whole body multi-slice magnetic resonance imaging (MRI) was used to estimate skeletal muscle mass and adipose tissue.

This study, which was among the first to describe and compare the relationship of skeletal muscle to bone using both MRI and DXA estimates, demonstrated that greater skeletal muscle mass was associated with greater bone mineral content (p<0.001). The skeletal muscle mass assessed by MRI provided a better model for the relationship of skeletal muscle to bone compared with assessment by DXA for predicting bone mineral content. The proportion of skeletal muscle mass in non-bone lean body mass was significantly associated with greater bone mineral content adjusted for total non-bone lean body mass. Children of Hispanic origin had greater bone mineral content compared to other race and ethnic groups after adjusting for sex, age, adipose tissue, skeletal muscle mass, and height.


* To determine whether skeletal muscle mass assessed by DXA or by MRI were better predictors of bone mineral content compared with non-bone lean body mass after adjusting for sex, age, race or ethnicity, and Tanner stage, linear regression model as determined by R2 statistic was used.

Reference
Dorsey KB, John C Thornton JC, Heymsfield SB, Gallagher D. Greater lean tissue and skeletal muscle mass are associated with higher bone mineral content in children. Nutrition & Metabolism 2010, 7:41 doi:10.1186/1743-7075-7-41

Article URL http://www.nutritionandmetabolism.com/content/7/1/41