ABSTRACT
Objective Due to the accelerated growth of Chinese children, the secular trend of accelerated skeletal development was observed in this study in order to provide the evidence for using the standards of skeletal maturity in reason.Methods The subjects were the children from two skeletal development surveys in 1980s and 2000s. The appearance age and fusion age of ossification centers in hand and wrist were calculated using the probit regression analysis, and the skeletal ages of children from the survey in 2000s were estimated by CHN method. The CHN skeletal ages were compared with calendar ages. Results Compared with the children in 1960s, the appearance ages and fusion ages of the ossification centers were all advanced in children in 1980s. Compared with the children in 1980s, the metacarpals and phalanges of children in 2000s were advanced by 0.5-1.0 year at age of appearance of ossification centers and 1.0 year in boys and 1.0-1.5 years in girls at the ages of fusion ossification centers. The ages of complete ossification of radius and ulna in children in 2000s were advanced by 0.4 year in boys and 0.3 year in girls. The differences between CHN skeletal age and chronological age of all age groups in 2000s were 0.3-1.1 year in boys and 0.2-1.0 year in girls. Conclusions In the last 40 years, the secular trend of accelerated skeletal development was presented in Chinese children. It should be cautious to estimate the contemporary Chinese children when using the skeletal norms of 1960s or 1980s.