Forensic Age Estimation In Chinese Han Female Living Teenagers With Limb Joint Radiographs

Objective:To analysis the histological characters and X-ray imaging regularities of epiphyses, which are from sternal end of clavical and the left side of shoulder, elbow, carpal, hip, knee and ankle joints in Chinese Han normal teenagers,and make medicolegal expertise methods and X-ray criterias by using X-ray signs of epiphysis growth of multi-parts and multi-indexes in living teenagers, which are utilized to estimate age associately. In order to resolve the medicolegal expertise of 14,16 and 18 years, which are of great significance to our law.Methods:①To investigate X-ray signs of epiphysis growth of the joints in Chinese Han normal teenagers, then selected 24 epiphyses as indexes which can reflect the age very well; meanwhile, to enact X-ray staging criteria of teenager's skeletal growth by quod viding the achievements of different parts'stage of skeletal growth completed by authoritories at home and abroad.②Radiographs were taken from 838 normal Chinese Han female subjects aged from 11 to 20 years old including sternal end of clavical and the left side of shoulder, elbow, carpal, hip, knee and ankle joints,which were from Central China, Southern China and Eastern China. Then read and recorded the 24 osteal loci in accordance with the grading criteria of skeletal growth of teenagers. The influencing factors such as: height, body mass and location were all taken into account. Then calculate 95% Reference Range and 95% Confidence Interval of epipysis arrest and appearance ages of the 24 osteal loci, to statistics the frequency distribution of different grades of the same index in different age groups. Pearson and spearman correlations and proc nlin analysis were applied to find the optimal model fitting of relationship between ossification stages of the indexes and chronological age. Fisher's linear discriminant method was used to determine age of 14, 16 and 18. All statistic procedures were finished by SPSS 11.0 and SAS 8.1.ResuLts:①X-ray staging criteria of teenager's skeletal growth were enacted. The stage value of the 24 skeletal age indexes were differently ranged from 2 stages o 8 stages. The stage numbers of different indexes of the single joint are respective alike or proximal, it shows that the time of different epiphysial growth in identical joints has isochromism.②We arrived at Mean,SD,SE,95% Reference Range and 95% Confidence Interval of epipysis arrest and appearance ages of the 24 osteal loci. It shows that skeletal development of Chinese teenagers has developed ahead.③Among the frequency distribution,we made some standard atlases of different age groups.After tested by the samples, we found that when the precision is±0.5 years, the accuracy of atlases is 70.0%; but when the precision is high to±1.0 years, the accuracy is over to 90.0%.④Also we constructed several combining multiple regression mathematical models and established Fisher's discriminatory analysis equations which are used to determine whether the chronological age of Chinese Han female teenagers has been to 14,16 and 18 years old or not. The highest accuracy of those multiple regression mathematical models in±1.0 and±1.5 years are 78.46% and 93.85% respectively, and the highest accuracy of Fisher's discriminatory analysis equations is 87.2%.Conclusion:①This staging criteria has the merits of extensive skeletal growth indexes, applicable to wide age range and strong maneuverability, thus, it established a favourable fundamental platform for evaluating skeletal age of living subjects in forensic medicine in China.②The time of punctum ossificationis appearance and epiphysis arrest has been updated greatly. It also made the methods and conclusions much more scientific and accurate.③Compared with the data of 1950s'and 1960s', skeletal development of Chinese teenagers has developed ahead. The age at which ossification centre appeared and epiphysis arrested has been earlier by 2~3 years.④The mathematical models proposed in this study have provided some new methods to current forensic age estimation.⑤These infrequent imaging materials has the merits of large samples, more locations, grate age span and more parts et al. It is fit for the modern bone age research in our country, and it also made infarctate foundatins to the future study.