Is there any correlation between skeletal and chronological age on basis of gender and age in Korean children? An analysis based on RUS method

Objectives To Wnd out skeletal age maturation in Korean children and to know if there is any correlation between skeletal and chronological age on basis of gender and age in Korean children. Study design A cross-sectional study in 350 (174 boys, 176 girls) Korean children aged between 5 and 18. Methods Left hand radiographs of 350 Korean children were evaluated for skeletal age using RUS (TW3) scoring system which was compared according to gender and age. We also compared eYcacy of TW3 method in diVerent age groups in both genders. Results Chronological age was 12.13 ± 3.7 years for males and 11.90 ± 3.8 years for females and RUS bone age was 10.78 ± 3.5 years and 11.32 ± 3.7 years, respectively, which showed less skeletal maturity in Korean children (P < 0.0001) compared to chronological age. Although RUS age is lagging behind the chronological age, comparing it with chronological age in the age groups <7, 7-10, 11-13, and 14-18 years showed concordance correlation coeYcient (CCC) 0.966 and 0.978, respectively for females and males, which showed that RUS method is equally reliable in measuring the bone age at any age and in any gender. Conclusion We recommend RUS method to measure the skeletal age, and to consider RUS not chronological age before interventional procedures in Korean children by waiting for a longer time to match the bone age equal to chronological age.