Comparative study of Gilsanz-Ratib digital atlas and Greulich-Pyle atlas for bone age estimation in a Chinese sample

The applicability of the Gilsanz-Ratib (GR) digital atlas to bone age (BA) determination in China has not been evaluated.

To compare the validity of GR and the Greulich-Pyle (GP) atlas in BA determination for children in Shanghai.

Left-hand radiographs of 243 girls and 375 boys aged 0-13 years were obtained for suspected trauma. They were divided into eight sub-groups according to gender and age (0-3, 3-7, 7-10 and 10-13 years). Radiographs were read by two radiologists, using both GP and GR atlases. The differences between BA and calendar age (CA) were analysed. The inter- and intra-observer consistency was evaluated.

Pearson's correlation coefficients indicated a strong positive correlation between methods and between raters. The differences between BA and CA of two sub-groups (10-13-year-old boys, GR; 0-3-year-old girls, GP) were not only statistically significant, but exceeded 1 SD, suggesting biological significance.

Both atlases can be used on most age groups. However, the GR atlas is not recommended in boys aged 10-13 years, while the GP atlas is not suitable for girls aged 0-3 years. Therefore, the use of the GP or GR atlas is practical, depending on the age of the child.