Comparison of radiogrammetrical metacarpal indices in children and reference data from the First Zurich Longitudinal Study.

Background: A number of radiogrammetrical metacarpal indices are in use, some of which have been adapted for children.

Objective: The purpose of this study was to compare four known indices-bone mineral density (BMD), relative cortical area, Exton-Smith index, bending breaking resistance index-and the more recently defined pediatric bone index (PBI) according to the two criteria of minimum height dependence and minimum variability in children of equal bone age.

Materials And Methods: A total of 3,121 left-hand radiographs from 231 healthy Caucasian children ranging in age from 3 to 19 years old were analysed using BoneXpert®, a programme for automatic analysis of hand radiographs and assessment of bone age.

Validation of bone age methods by their ability to predict adult height.

Aim: Several bone age (BA) methods are in use today. The aim of this study was to introduce a framework for assessing the validity of a BA method by its ability to predict adult height (H) and to apply it to manual ratings based on Greulich-Pyle (GP) and Tanner-Whitehouse 3 (TW) and to the fully automated BoneXpert method.

Material: The study used X-rays of 232 children from the First Zurich Longitudinal Study recorded close to each anniversary.

Automatic determination of left- and right-hand bone age in the First Zurich Longitudinal Study.

Background/aims: A more advanced bone age (BA) has been reported for the left hand relative to the right hand, while another study has found no such effect. The aim was to study the average difference of automated BoneXpert BA determination (left- vs. right-hand) for normal children, examine the precision of automatic BA and provide a BA reference for normal Caucasian children.