Age assessment of Chinese Tibetan twins using multiple skeletal age estimation methods: A case report

Abstract

This case presents a unique age estimation involving Chinese Tibetan twins, where one of them has been arrested for alleged rape. His parents claimed he was about 13 years old without providing any official age documentation. Since age is important in criminal proceedings in China, bone age estimation was conducted to determine the chronological age of the twins. The twins underwent a physical examination, X-rays of the left hand/wrist, and pelvis, and a CT scan of the clavicle. Two age estimation standards in China were used: "Skeletal Maturity and Assessment Methods of Hand and Wrist for Chinese" (China-05 standard), and "Technical Specifications for Skeletal Age Evaluation of Han Population Teenagers" (TSSHPT standard). The bone radiographs showed that most of the twins' epiphyseal development was similar, with only slight differences observed in the distal radius, distal ulna, and iliac crest apophysis. The results of the two methods showed differences in the range of predicted ages. Applying the RUS-CHN method to hand/wrist images, the estimated age of the suspect was determined to be 16-16.5 years old, while his brother's age was 15.5-16 years old. Applying the TSSHPT standard to all three images, the estimated age of the suspect was 17-17.5 years old, while his brother's age was estimated to be 16.5-17 years old. In this case, two commonly used methods for age estimation were introduced. The disparity in age estimations using the RUS-CHN and TSSHPT standards, with the age of the suspect ranging from 16 to 17.5 years. This case revealed that the choice of bone age estimation method can significantly impact the result of estimated age, which has important implications for legal proceedings. Additionally, the minor differences in skeletal maturity between the twins emphasize the need to account for individual variations, even among genetically similar individuals. Furthermore, this case contributes to the broader discourse on the effectiveness of skeletal age estimation methods across diverse populations, underscoring the necessity for tailored evaluation standards that consider genetic and environmental diversity.

Keywords: Bone age estimation; China-05 standard; Epiphysis development; TSSHPT standard; Twins.