Automated determination of bone age in a modern chinese population.

Rationale and Objective. Large studies have previously been performed to set up a Chinese bone age reference, but it has been difficult to compare the maturation of Chinese children with populations elsewhere due to the potential variability between raters in different parts of the world. We re-analysed the radiographs from a large study of normal Chinese children using an automated bone age rating method to establish a Chinese bone age reference, and to compare the tempo of maturation in the Chinese with other populations. Materials and Methods. X-rays from 2883 boys and 3143 girls aged 2-20 years from five Chinese cities, taken in 2005, were evaluated using the BoneXpert automated method. Results. Chinese children reached full maturity at the same age as previously studied Asian children from Los Angeles, but 0.6 years earlier than Caucasian children in Los Angeles. The Greulich-Pyle bone age method was adapted to the Chinese population creating a new bone age scale BX-China05. The standard deviation between BX-China05 and chronologic age was 1.01 years in boys aged 8-14, and 1.08 years in girls aged 7-12. Conclusion. By eliminating rater variability, the automated method provides a reliable and efficient standard for bone age determination in China.

[Relationship of certain skeletal maturity indicators of hand and wrist with adolescent growth spurt].

OBJECTIVE: To investigate the relationship of certain skeletal maturity indicators of hand and wrist with adolescent growth spurt. METHODS: 14 757 normal urban children, 7373 boys and 7384 girls, aged 7 - 20, all of Han nationality, from Shanghai, Guangzhou, Wenzhou, Dalian, and Shijiazhuang underwent measurement of height and weight, and left wrist anterior-posterior radiography. The incremental curve was fitted graphically according to the differences between the means for height at series ages. The ages of attainment of eleven skeletal indicators were defined by regression analysis for middle phalange 3, radius, and adductor sesamoid of the first finger. RESULTS: The accelerative phase of adolescent growth spurt was accompanied by becoming square of middle phalange 3 and the appearance of adductor sesamoid of the first finger. Peak growth velocity (PGV) was reached at about the time of epiphysis capping in middle phalange 3 and ossification of the adductor sesamoid of first finger. Decelerated phase of growth was indicated by the beginning of epiphysis fusion in radius and full maturity in adductor sesamoid of first finger. When the epiphysis of middle phalange 3 and the half of epiphysis of radius were respectively fused with their diaphyses, the growth spurt was ended. CONCLUSION: Certain skeletal maturity indicators of hand and wrist can be used to indicate the period of adolescent growth that a child has reached.

[Reference values of differences between TW3-C RUS and TW3-C Carpal bone ages of children from five cities of China].

OBJECTIVE: The determination of skeletal maturity has an important role in pediatric clinical practice, especially in relation to endocrinological problems and growth disorders, and it is frequently useful in diagnosis and monitoring treatment. It has been suggested that the difference between radius, ulna and short bonse (RUS) and carpal may be of differential diagnostic significance. However, no data on comparison among bone ages of Chinese children are available. The differences between TW3-Chinese RUS (TW3-C RUS) and TW3-Chinese Carpal (TW3-C Carpal) bone age of Chinese children were observed in this study to provide references for skeletal development estimation. METHODS: Totally 9408 Han healthy children (5066 boys, 4302 girls) aged 1.5 - 13.5 years from 5 cities of China were enrolled in this study. The bone ages of the children were estimated by TW3-C RUS and TW3-C Carpal. The Z score curves of the differences between them were fitted by BCPE distribution and the goodness-of-fit of Box-Cox power exponential distribution (BCPE) models were assessed by Q-test and percents of cases of sample below the fitted percentile curves. RESULTS: The means of the differences between TW3-C RUS and TW3-C Carpal were -0.19 - 0.17 over the age 2.0 - 13.5 years in boys and -0.12 - 0.13 from age 1.5 - 11.5 years in girls. The standard deviations were respectively 0.47 - 1.01 years for boys and 0.49 - 0.82 years for girls. The degrees of freedom, with respect to the parameter curves from BCPE distribution, were selected and the percentile curves were fitted by BCPE. The differences between percents of cases below the fitted percentile curves and expected values were all under 0.66%, exception of difference for 90th percentile in girls. CONCLUSIONS: The differences between TW3-C RUS and TW3-C Carpal varied with age, the standard deviations increased gradually before 4.5 years of age in boys and 4 years of age in girls, and afterwards the variations decreased steadily until the TW3-C Carpal has reached full maturity. However, there was sex diversity in the extent of the variations. The differences between TW3-C RUS and TW3-C Carpal for boys were evidently greater than that for girls. The sex difference decreased progressively after 10 years. The proposed Z scores curves charts should provide reference for clinical practice.

Standards of TW3 skeletal maturity for Chinese children.

This study included 17 401 normal Han urban children aged 1-20 years from five cities in China in 2005. The skeletal maturity scores were assessed by the Tanner-Whitehouse 3 (TW3) method, and the smoothed centiles curves of scores (TW3-Chinese RUS and TW3-Chinese Carpal) were calculated using the LMS method. The skeletal maturity of the Chinese is approximately the same as Europeans in childhood, but the extent of TW3-RUS skeletal maturity advance in puberty and the ages of complete maturity of TW-Carpals are evidently more advanced in the Chinese.