Determination of bone age and bone mass in modern United Kingdom and Saudi Arabian populations.

The Greulich & Pyle (G&P) and Tanner & Whitehouse (TW) methods are frequently used to determine bone age. The applicability of these methods for populations who are of different ethnicity or socioeconomic status to the reference standard has been subjected to questions. Therefore, a systematic review was undertaken to evaluate the applicability of the G&P atlas for four major ethnicities. The G&P standard appeared imprecise when applied to Asian male and African female populations.
The applicability of the G&P and TW3 to modern population from the United Kingdom and Saudi Arabia was assessed. The automatic software called (BoneXpert) which calculates bone age beside on the G&P and TW3, was used. The software can eliminate observer variability and provide timesaving solution. In total 821 hand radiographs (426 males) were included on the analysis. In the UK, the G&P atlas appeared to be applicable while The TW3 consistently underestimates the age of females by an average of 5 months. Furthermore, significant differences between BA and CA were apparent in Saudi Arabian males when using the G&P atlas and TW3 method.
The added advantage of BoneXpert is that bone mass can be assessed from left hand radiographs. However, results from 291 patients, in which their dual energy x-ray absorptiometry (DXA) and hand radiographs have been acquired on the same day, showed weak correlation between DXA and bone mass calculated by the software.
The BoneXpert performance with regard to images taken using modalities other than conventional radiography was evaluated. Nevertheless, another advantage is that children are more likely to expose to much lower radiation dose from hand-wrist DXA compare to left hand radiographs. The low quality of DXA prohibits the use of BoneXpert software for the automatic determination of bone age while the TW3 cannot be determined manually from the hand-wrist DXA.