Dr Melton has served as a speaker for Amgen, Merck & Co., and Procter & Gamble. All other authors state that they have no conflicts of interest.
Contribution of In Vivo Structural Measurements and Load/Strength Ratios to the Determination of Forearm Fracture Risk in Postmenopausal Women
Article first published online: 29 MAY 2007
Copyright © 2007 ASBMR
Journal of Bone and Mineral Research
Volume 22, Issue 9, pages 1442–1448, September 2007
How to Cite
Melton, L. J., Riggs, B. L., van Lenthe, G. H., Achenbach, S. J., Müller, R., Bouxsein, M. L., Amin, S., Atkinson, E. J. and Khosla, S. (2007), Contribution of In Vivo Structural Measurements and Load/Strength Ratios to the Determination of Forearm Fracture Risk in Postmenopausal Women. J Bone Miner Res, 22: 1442–1448. doi: 10.1359/jbmr.070514
- Issue published online: 4 DEC 2009
- Article first published online: 29 MAY 2007
- Manuscript Accepted: 22 MAY 2007
- Manuscript Revised: 4 APR 2007
- Manuscript Received: 24 OCT 2006
- bone quality;
- Colles' fracture;
Bone structure, strength, and load-strength ratios contribute to forearm fracture risk independently of areal BMD.
Introduction: Technological and conceptual advances provide new opportunities for evaluating the contributions of bone density, structure, and strength to the pathogenesis of distal forearm fractures.
Materials and Methods: From an age-stratified random sample of Rochester, MN, women, we compared 18 with a distal forearm fracture (cases) to 18 age-matched women with no osteoporotic fracture (controls). High-resolution pQCT was used to assess volumetric BMD (vBMD), geometry, and microstructure at the ultradistal radius, the site of Colles' fractures. Failure loads in the radius were estimated from microfinite element (μFE) models derived from pQCT. Differences between case and control women were assessed, and the risk of fracture associated with each variable was estimated by logistic regression analysis.
Results: Given similar heights, estimated loading in a fall on the outstretched arm was the same in cases and controls. However, women with forearm fractures had inferior vBMD, geometry, microstructure, and estimated bone strength. Relative risks for the strongest determinant of fracture in each of the five main variable categories were as follows: BMD (total vBMD: OR per SD change, 4.2; 95% CI, 1.4–12), geometry (cortical thickness: OR, 4.0; 95% CI, 1.4–11), microstructure (trabecular number: OR, 2.3; 95% CI, 1.02–5.1), and strength (axial rigidity: OR, 3.8; 95% CI, 1.4–10); the factor-of-risk (fall load/μFE failure load) was 24% greater (worse) in cases (OR, 3.0; 95% CI, 1.2–7.5). Areas under ROC curves ranged from 0.72 to 0.82 for these parameters.
Conclusions: Bone geometry, microstructure, and strength contribute to forearm fractures, as does BMD, and these additional determinants of risk promise greater insights into fracture pathogenesis.