Estimating body mass and composition from proximal femur dimensions using dual energy x-ray absorptiometry

Emma Pomeroy,Jonathan C K Wells,Veena Mushrif-Tripathy,Meghan K Shirley,Bharati Kulkarni,Sanjay Kinra,Tim J Cole,Jay T Stock

doi:10.1007/s12520-018-0665-z

Abstract

Body mass prediction from the skeleton most commonly employs femoral head diameter (FHD). However, theoretical predictions and empirical data suggest the relationship between mass and FHD is strongest in young adults, that bone dimensions reflect lean mass better than body or fat mass and that other femoral measurements may be superior. Here, we generate prediction equations for body mass and its components using femoral head, neck and proximal shaft diameters and body composition data derived from dual-energy x-ray absorptiometry (DXA) scans of young adults (n = 155, 77 females and 78 males, mean age 22.7 ± 1.3 years) from the Andhra Pradesh Children and Parents Study, Hyderabad, India. Sex-specific regression of log-transformed data on femoral measurements predicted lean mass with smaller standard errors of estimate (SEEs) than body mass (12–14% and 16–17% respectively), while none of the femoral measurements were significant predictors of fat mass. Subtrochanteric mediolateral shaft diameter gave lower SEEs for lean mass in both sexes and for body mass in males than FHD, while FHD was a better predictor of body mass in women. Our results provide further evidence that lean mass is more closely related to proximal femur dimensions than body or fat mass and that proximal shaft diameter is a better predictor than FHD of lean but not always body mass. The mechanisms underlying these relationships have implications for selecting the most appropriate measurement and reference sample for estimating body or lean mass, which also depend on the question under investigation.

Highlights

Research continues to address the problem of estimating body mass from the skeleton since body size is an important characteristic of a species or population linking many aspects of School of Hygiene and Tropical Medicine, London, UK 5 ADaPt Project, PAVE Research Group, Department of Archaeology and Anthropology, University of Cambridge, Cambridge, UK 6 UCL Great Ormond Street Institute of Child Health, UCL, London, UK their behaviour, diet, mortality risk and life history (Charnov 1993; Harvey and Clutton-Brock 1985; Harvey and Read 1988; Robson and Wood 2008; Sibly and Brown 2007; Will et al 2017)
A number of studies have focussed on using femoral head diameter (FHD) to estimate body mass, and the three most commonly used equations are those of McHenry (1992), Grine et al (1995) and Ruff et al (1991)
Example scatterplots for body, lean and fat mass against femur subtrochanter mediolateral diameter are shown in Fig. 2; those for other femoral measurements are similar

Summary

Introduction

Ordinary least squares (OLS) regression was used to derive equations to estimate body, lean and fat mass from each of the proximal femur measurements. Our study demonstrates that in a sample of young adults from the region around Hyderabad, India, lean mass can be estimated from measurements of the proximal femur with an SEE of 12.2%.

Objectives

Results

Conclusion