Download PDF
Exp Clin Endocrinol Diabetes 2011; 119(6): 321-326
DOI: 10.1055/s-0031-1277139
Article

© J. A. Barth Verlag in Georg Thieme Verlag KG Stuttgart · New York

The Functional Muscle-Bone Unit in Obese Children – Altered Bone Structure Leads to Normal Strength Strain Index

S. Ehehalt1 , G. Binder1 , N. Schurr1 , C. Pfaff1 , M. B. Ranke1 , R. Schweizer1  for the DISKUS-Study Group 
  • 1Pediatric Endocrinology and Diabetology, University Children's Hospital, Tuebingen, Germany
Further Information

Publication History

received 13.07.2010 first decision 11.02.2011

accepted 04.04.2011

Publication Date:
06 May 2011 (online)

Also available at
    Permissions and Reprints

Abstract

Obese children have a twofold increased risk of fracture of the forearm compared to non-obese children.

Objective: To investigate bone strength and bone structure of the forearm, and the relationship between muscle and bone in obese children.

Methods: The study-group consisted of 84 (40 female) overweight children (mean (SD)) age 11.8 (3.2) years, BMI 29.0 (5.1) kg/m2). Bone geometry and strength were measured at the proximal radius of the non-dominant forearm (65% measurement site) by means of pQCT (XCT 2000). Bone mineral density and lean mass of the total body was determined by means of DXA (Lunar, DPXL/PED). Results were compared to reference values by calculating age (SDSCA) and height-age (SDSHA) dependent standard deviation scores (SDS).

Results: Cortical density, −1.11 (1.74) SDSHA, −0.45 (1.52) SDSCA; cortical thickness, −1.46 (1.33) SDSHA, −1.01 (1.46) SDSCA; cortical area, −0.42 (1.31) SDSHA, 0.26 (1.58) SDSCA; total bone area +2.21 (1.47) SDSHA, 2.91 (1.80) SDSCA, marrow area +3.12 (2.29) SDSHA, 3.37 (2.38) SDSCA; strength strain index +0.10 (1.10) SDSHA, 0.95 (1.57) SDSCA. These changes in bone structure were independent from pubertal stage. Measurements revealed correlations between muscle area and SSI (R2=0.67, p<0.001), and muscle mass and bone mineral content (DXA; R2=0.81, p<0.001).

Conclusion: Low cortical density, normal cortical area and increased total bone area led to a normal strength strain index adjusted both for height and for age. We assume that this normal bone strength is not appropriate for the higher kinetic energy of impact in case of a fall in overweight children.

Key words

obesity - children - functional muscle-bone unit - DXA - pQCT

References

  • 1 Aksglaede L, Juul A, Olsen LW. et al . Age at Puberty and the Emerging Obesity Epidemic.  PLoS ONE. 2009;  4 e8450
    Google Scholar
  • 2 Bös K, Opper E, Woll A. Fitness in der Grundschule.  Haltung und Bewegung. 2002;  22 5-25
    Google Scholar
  • 3 Cole TJ, Freeman JV, Preece MA. Body mass index reference curves for the UK, 1990.  Arch Dis Child. 1995;  73 25-29
    Google Scholar
  • 4 Davidson PL, Goulding A, Chalmers DJ. Biomechanical analysis of arm fracture in obese boys.  J Paed Child Health. 2003;  39 657-664
    Google Scholar
  • 5 De Schepper J, Van den Broeck M, Jonckheer MH. Study of lumbar spine bone mineral density in obese children.  Acta Paediatr. 1995;  84 313-315
    Google Scholar
  • 6 Fischer S, Milinarsky A, Giadrosich V. et al . X-ray absorptiometry of bone in obese and eutrophic children from Valparaiso, Chile.  J Rheumatol. 2000;  27 1294-1296
    Google Scholar
  • 7 Frost HM, Schönau E. The “muscle-bone unit” in children and adolescents: a 2000 overview.  J Pediatr Endocrinol Metab. 2000;  13 571-590
    Google Scholar
  • 8 Frost HM. Changing concepts in skeletal physiology: Wolff's law, the mechanostat, and the “Utah paradigm”.  Am J Hum Biol. 1998;  10 599-505
    Google Scholar
  • 9 Hasanoglu A, Bideci A, Cinaz P. et al . Bone mineral density in childhood obesity.  J Pediatr Endocrinol Metab. 2000;  3 307-311
    Google Scholar
  • 10 Hasegawa Y, Schneider P, Reiners C. et al . Estimation of the architectural properties of cortical bone using peripheral quantitative computed tomography.  Osteoporos Int. 2000;  11 36-42
    Google Scholar
  • 11 Johnson J, Dawson-Hughes B. Precision and stability of dual-energy X-ray absorptiometry measurements.  Calcif Tissue Int. 1991;  49 174-178
    Google Scholar
  • 12 Klein KO, Larmore KA, de Lancey E. et al . Effect of obesity on estradiol level, and its relationship to leptin, bone maturation, and bone mineral density in children.  J Clin Endocrinol Metab. 1998;  83 3469-3475
    Google Scholar
  • 13 Kurth BM, Schaffrath R. Die Verbreitung von Übergewicht und Adipositas bei Kindern und Jugendlichen.  Bundesgesundheitsbl – Gesundheitsforschung – Gesundheitsschutz. 2007;  50 736-743
    Google Scholar
  • 14 Leonard MB, Shults J, Wilson BA. et al . Obesity during childhood and adolescence augments bone mass and bone dimensions.  Amer J Clin Nutr. 2004;  80 514-523
    Google Scholar
  • 15 McCormick DP, Ponder SW, Fawcett HD. et al . Spinal bone mineral density in 335 normal and obese children and adolescents: evidence for ethnic and sex differences.  J Bone Miner Res. 1991;  6 507-513
    Google Scholar
  • 16 Morano M, Colella D, Robazza C. et al . Physical self-perception and motor performance in normal-weight, overweight and obese children.  Scand J Med Sci Sports. 2010 Jan 31; 
    Google Scholar
  • 17 Pintauro SJ, Nagy TR, Duthie CM. et al . Cross-calibration of fat and lean measurements by dual-energy X-ray absorptiometry to pig carcass analysis in the pediatric body weight range.  Am J Clin Nutr. 1996;  63 293-298
    Google Scholar
  • 18 Popkin BM, Gordon-Larsen P. The nutrition transition: worldwide obesity dynamics and their determinants.  Int J Oes Relat Metab Disord. 2004;  28 (S 03) 2-9
    Google Scholar
  • 19 Prader A, Largo RH, Molinari L. et al . Physical growth of Swiss children from birth to 20 years of age. First Zurich longitudinal study of growth and development.  Helv Paediatr Acta Suppl. 1989;  52 1-125
    Google Scholar
  • 20 Rauch F, Neu CM, Wassmer G. et al . Muscle analysis by measurement of maximal isometric grip force: new reference data and clinical applications in pediatrics.  Pediatr Res. 2002;  51 (4) 505-510
    Google Scholar
  • 21 Sayers A, Tobias JH. Fat mass exerts a greater effect on cortical bone mass in girls than boys.  J Clin Endocrinol Metab. 2010;  95 699-706
    Google Scholar
  • 22 Schönau E, Neu CM, Beck B. et al . Bone mineral content per muscle cross-sectional area as an index of the functional muscle-bone unit.  J Bone Miner Res. 2002;  17 1095-1101
    Google Scholar
  • 23 Schönau E. Problems of bone analysis in childhood and adolescence.  Pediatr Nephrol. 1998;  12 420-429
    Google Scholar
  • 24 Schönau E, Neu CM, Rauch F. et al . The development of bone strength at the proximal radius during childhood and adolescence.  J Clin Endocrinol Metab. 2001;  86 613-618
    Google Scholar
  • 25 Schweizer R, Martin DD, Haase M. et al . Similar effects of long-term exogenous growth hormone (GH) on bone and muscle parameters: a pQCT study of GH-deficient and small-for-gestational-age (SGA) children.  Bone. 2007;  41 875-881
    Google Scholar
  • 26 Schweizer R, Martin DD, Schwarze CP. et al . Cortical bone density is normal in prepubertal children with growth hormone (GH) deficiency, but initially decreases during GH replacement due to early bone remodeling.  J Clin Endocrinol Metab. 2003;  88 5266-5272
    Google Scholar
  • 27 Tanner JM. Normal growth and techniques of growth assessment.  Clin Endocrinol Metab. 1986;  15 411-451
    Google Scholar
  • 28 Troiano RP, Briefel RR, Carroll MD. et al . Energy and fat intakes of children and adolescents in the United States: data from the national health and nutrition examination surveys.  Am J Clin Nutr. 2000;  72 1343-1353
    Google Scholar
  • 29 Van der Sluis I, de Ridder MA, Boot AM. et al . Reference data for bone density and body composition measured with dual energy X ray absorptiometry in white children and young adults.  Arch Dis Child. 2002;  87 341-347
    Google Scholar
  • 30 Wetzsteon RJ, Petit MA, Macdonald HM. et al . Bone structure and volumetric BMD in overweight children: a longitudinal study.  J Bone Mineral Res. 2008;  23 1946-1953
    Google Scholar
  • 31 Wosje KS, Knipstein BL, Kalkwarf HJ. Measurement error of DXA: Interpretation of fat and lean mass changes in obese and non-obese children.  J Clin Densitom. 2006;  9 (3) 335-340
    Google Scholar
  • 32 Wey HE, Binkley TL, Beare TM. et al . Cross-sectional versus longitudinal associations of lean and fat mass with pQCT bone outcomes in children.  J Clin Endocrinol Metab. 2011;  96 106-114
    Google Scholar

APPENDIX

DISKUS-Study Group

Perikles Simon, Gutenberg University, Sports Medicine, Mainz, Germany;

Andre Lacroix, Jochen Hansel, Andreas Nieß, University Hospital for Internal Medicine, Sports Medicine, Tuebingen, Germany; Katrin Giel, Markus Schrauth †, Paul Enck, Stephan Zipfel, University Hospital for Internal Medicine, Department of Psychosomatic Medicine and Psychotherapy, Tuebingen, Germany; Jürgen Machmann, Fabian Springer, Verena Ballweg, Fritz Schick, Eberhard-Karls-University, Section on Experimental Radiology, Department of Diagnostic Radiology, Tuebingen, Germany; Michael S. Urschitz, Department of Neonatology, University Children's Hospital, Tuebingen, Germany; Andreas Neu, Hans Peter Haber, Department of Paediatrics, University Children's Hospital, Tuebingen, Germany; Huu Phuc Nguyen, Eberhard-Karls-University, Department of Medical Genetics, Tuebingen, Germany.

Correspondence

Dr. R. Schweizer

Pediatric Endocrinology and

Diabetology

University Children's

Hospital

Hoppe-Seyler-Straße 1

D-72076 Tuebingen

Germany

Phone: +49/7071/29 83781

Fax: +49/7071/29 4157

Email: roland.schweizer@gmx.de

      >