Although bone age plays a special role in determining the child's age, there are some variations in skeletal growth of different people. The aim of this study was to compare the bone age with chronological age of children aged 2-18 years old in order to recognize whether Greulich-Pyle (GP) method could be reliable for Iranian children? The standard radiograph of Left hand was taken in 40 healthy subjects, then the bone age was determined according to GP. Mean ± SD bone ages were delayed 1.12 ± 0.65, 0.82 ± 1.34 and 0.10 ± 0.51 years than the mean chronological ages in 2.99-5.99, 10-13.99 and 14-17.99 age group, respectively; and advanced -0.33 ± 3.12 years in the 6-9.99 age group. In BMI levels <18.5, 18.5-24.9, 25-29.9 and ≥30, Mean ± SD bone ages in males were delayed 2.25 ± 0.21, 0.14 ± 0.55, 0.87 ± 0.41 and 4.05 ± 0.70 years than the mean chronological ages, respectively. In BMI range of 18.5-24.9 and BMI ≥ 30, Mean ± SD bone age in females was delayed 0.50 ± 0.49 and 0.45 ± 0.63 years than the mean chronological ages, respectively. For BMI < 18.5, Mean ± SD bone age in females were advanced -0.40 ± 2.69 years than mean chronological ages. Considering these differences, Iranian boys may have a different pattern of bone growth from GP standards.
Keywords: Bone age; Chronological age; Determining of skeletal age based on Greulich-Pyle; Greulich-Pyle (GP).