Measures of the Forearm via a Portable Device: Ready for Prime Time?

Abstract

Measurement of areal bone mineral density (BMD) by dual-energy X-ray absorptiometry (DXA) is an important tool in the evaluation of bone health in children and adolescents, but available data in the pediatric population are limited, particularly in younger children. To address this issue, Hazell et al (1) present results from their study evaluating the correlation between areal BMD measures of the forearm by peripheral instantaneous X-ray imager (PIXI), a portable DXA device that affords BMD measures of the appendicular skeleton, compared with forearm measures by standard DXA in preschool-aged children. The study found that PIXI results correlated moderately well with areal BMD at the ultradistal radius as measured by DXA in boys and girls in this age group, suggesting that this tool holds promise as a skeletal assessment tool. The benefits of a portable DXA device are welldescribed, including use in field research in regions where standard DXA and peripheral quantitative computed tomography (pQCT) machines are not possible due to size and portability issues (2). The use of PIXI forearm measures in the adult population has yielded important data that might otherwise not have been feasible to obtain (3e5), and the measures have also been used in adolescent subjects (6,7). The low radiation dose associated with these devices is also noteworthy for use in a pediatric population. By applying this technology to younger children, this study provides an important foundation on which further studies can build. The ability