ABSTRACT
The interaction of body fat percentage and height with appendicular BMC for LBM was analyzed. Only body fat had significant negative correlation with the appendicular BMC for LBM. PURPOSE/INTRODUCTION: For the clinical evaluation of the functional muscle-bone unit, it was proposed to evaluate the adaptation of the bone to the acting forces. A frequently used parameter for this is the total body less head bone mineral content (TBLH-BMC) determined by dual-energy X-ray absorptiometry (DXA) in relation to the total body lean body mass (LBM). Body fat percentage seemed to correlate negatively and height positively with TBLH-BMC for LBM. It was supposed that appendicular BMC for LBM is a more accurate surrogate for the functional muscle-bone unit since appendicular LBM does not incorporate the mass of internal organs. The aim of this study was to analyze the interaction of body fat percentage and height with appendicular BMC for LBM. METHODS: As part of the National Health and Nutrition Examination Survey (NHANES) study, between the years 1999 and 2004, whole-body DXA scans on randomly selected Americans from 8 years of age were carried out. From all eligible DXA scans, three major US ethnic groups were evaluated (non-Hispanic Whites, non-Hispanic Blacks, and Mexican Americans) for further statistical analysis. RESULTS: For the statistical analysis, the DXA scans of 8190 non-Hispanic White children and adults (3903 female), of 4931 non-Hispanic Black children and adults (2250 female), and 5421 of Mexican American children and adults (2424 female) were eligible. Only body fat had a significant negative correlation with the appendicular BMC for LBM. CONCLUSIONS: Only body fat had significant negative correlation with appendicular BMC for LBM, and thus, should be addressed when evaluating functional muscle-bone unit.
Subject(s)
Adipose Tissue , Body Composition , Body Height , Bone and Bones , Muscle, Skeletal , Absorptiometry, Photon , Adolescent , Adult , Black or African American , Age Factors , Aged , Bone Density , Child , Female , Humans , Male , Mexican Americans , Middle Aged , Nutrition Surveys , Sex Factors , White PeopleABSTRACT
OBJECTIVES: Jumping mechanography provides robust motor function indicators among healthy children. The aim of the study was to assess the reproducibility and validity of jumping mechanography conducted as single two-legged jump (S2LJ) in children with cerebral palsy (CP). METHODS: 215 S2LJ investigations from a sample of 75 children with CP were eligible for evaluation. For the estimation of the reproducibility, only the baseline set of data per patient were used. Gross motor function was evaluated by the Gross Motor Function Measure (GMFM-66). In 135 S2LJ investigations, GMFM-66 was assessed within a week in the same child. This data was used for validity assessment. RESULTS: Coefficients of variation for the main outcome parameters ranged between 6.15-9.71%, except for jump height (CV%=27.3%). The intraclass correlation coefficients for peak velocity (Vmax) and peak power relative to body weight (Pmax/mass) was 0.927 and 0.931. Vmax and Pmax/mass were also the test parameters with the strongest correlation to the GMFM-66 score (⟩0.7). CONCLUSIONS: S2LJ assessed in the present study provided reproducible outcome measures particularly for Vmax and Pmax/mass in children with CP. Further, Vmax and Pmax/mass showed the strongest correlation with the GMFM-66 score and seem to be the most relevant evaluation criteria.
