Racial Differences in Growth Patterns of Children Assessed on the Basis of Bone Age

Purpose: To collect up-to-date data in healthy children to create a digital hand atlas (DHA) that can be used to evaluate, on the basis of the Greulich and Pyle atlas method, racial differences in skeletal growth patterns of Asian, African American, white, and Hispanic children in the United States. Materials and Methods: This retrospective study was HIPAA compliant and approved by the institutional review board. Informed consent was obtained from all subjects or their guardians. From May 1997 to March 2008, a DHA containing 1390 hand and wrist radiographs obtained in male and female Asian, African American, white, and Hispanic children with normal skeletal development was developed. The age of subjects ranged from 1 day to 18 years. Each image was read by two pediatric radiologists working independently and without knowledge of the subject's chronologic age, and evaluation was based on their experience with the Greulich and Pyle atlas. Statistical analyses were performed with the paired-samples t test and analysis of variance to study racial differences in growth patterns. P <= .05 indicated a significant difference. Results: Bone age (P <= .05) was significantly overestimated in Asian and Hispanic children. These children appear to mature sooner than their African American and white peers. This was seen in both male and female subjects, especially in girls aged 10 - 13 years and boys aged 11 - 15 years. Conclusion: Ethnic and racial differences in growth patterns exist at certain ages; however, the Greulich and Pyle atlas does not recognize this fact. Assessment of bone age in children with use of the Greulich and Pyle atlas can be improved by considering the subject's ethnicity. (C) RSNA, 2008