Bone development shows certain regularity with age. The regularity can be used to infer age and serve many fields such as justice, medicine, archaeology, etc. As a non-invasive evaluation method of the epiphyseal development stage, MRI is widely used in living age estimation. In recent years, the rapid development of machine learning has significantly improved the effectiveness and reliability of living age estimation, which is one of the main development directions of current research. This paper summarizes the analysis methods of age estimation by knee joint MRI, introduces the current research trends, and future application trend.
Epiphyses/diagnostic imaging* ; Age Determination by Skeleton/methods* ; Reproducibility of Results ; Magnetic Resonance Imaging/methods* ; Knee Joint/diagnostic imaging*

Objective To develop mathematical models for skeletal age determination with multiple statistic method based on the correlation between age and the growth of the epiphysis of extremitas sternalis of clavicle in Shanxi adolescents. Methods The 562 Shanxi sternoclavicular joint samples （454 cases of modelling, 108 cases of external verification） were scanned by the thin-section computed tomography. After volume rendering was obtained, indicators such as area of epiphysis, area of metaphysis, longest diameter of epiphysis and longest diameter of metaphysis of both extremitas sternalis of clavicle were collected. Indicators such as the ratio of area of epiphysis to area of metaphysis, and the ratio of longest diameter of epiphysis to longest diameter of metaphysis of both sides were calculated. Then multiple linear regression and random forest discriminant models were used to build mathematical models for age determination of adolescents. Results The obtained indicators exhibited a strong correlation with age （r>0.85）. The multiple linear regression model for males and females （all 4 indicators entering the model） based on the ratio of longest diameter of epiphysis to longest diameter of metaphysis and the ratio of area of epiphysis to area of metaphysis had an internal validation accuracy rate （±1.0 year） of over 92% and 108 cases had an external validation accuracy rate of over 70% （±1.0 year）. The out of bag error rates of random forest discriminant models were less than 2% for people over 18.0 years old （≥18.0 years old） and under 18.0 years old. The external validation accuracy rates of the 108 cases were over 80%. Conclusion The regression and discriminant models established in this study have certain reliability and accuracy and can be used in age determination of Shanxi adolescents.
Adolescent ; Age Determination by Skeleton ; Clavicle/diagnostic imaging* ; Epiphyses/diagnostic imaging* ; Female ; Forensic Anthropology ; Humans ; Male ; Models, Theoretical ; Osteogenesis ; Reproducibility of Results

Combined type III Monteggia fracture dislocation and ipsilateral distal radial epiphyseal fracture is a very rare injury. Because of difficulty in performing the proper clinical evaluation of a child in an acute injury state, one of the components of this combined injury may be missed. We report a ten-year-old male child with this kind of injury where the Monteggia lesion was initially missed at the emergency department. Later we found the combined epiphyseal fracture of distal radius and Monteggia lesion in the ipsilateral side of the same limb which was managed by closed reduction and K-wire fixation. Bony union as well as wrist and elbow motion was complete 3 months after surgical intervention.
Child ; Epiphyses ; diagnostic imaging ; injuries ; Humans ; Male ; Monteggia's Fracture ; diagnostic imaging ; surgery ; Probability ; Radius Fractures ; diagnostic imaging ; surgery

OBJECTIVE: To estimate the chronological age of Han teenagers in Sichuan by the epiphyses development characteristics of iliac crest and ischial tuberosity in X-ray digital images. METHODS: According to TW2 classification principle, combining with the age range of our subjects and epiphyses development regularity, the degree of epiphyses development of iliac crest and ischial tuberosity had been divided into 8 grades (0-7) and 7 grades (0-6), respectively. Based on the degrees, the pelvic X-rays digital images of 691 samples of 16-20 aged teenagers were read and statistically analyzed by SPSS 19.0 software. The multiple linear regression equation was established by skeletal age (Y), development degree of iliac crest epiphyses (X1) and ischial tuberosity epiphyses (X2). RESULTS: There were no statistical differences between two sides of epiphyses development of iliac crest and ischial tuberosity (P>0.05). There were no statistical difference between genders (P>0.05). The re-substitution method of the samples showed that the accuracy of equation as Y=15.269+0.444X1+0.236 X2 was high. The result of the re-substitution method showed a high accuracy of the equation. CONCLUSION The multiple linear regression equation could be used to identify the skeletal age for providing the scientific basis to identify the 18-year-old Han population in Sichuan.
Adolescent ; Age Determination by Skeleton/methods* ; Age Factors ; Asian People/ethnology* ; Bone Development/physiology* ; China/ethnology* ; Epiphyses/diagnostic imaging* ; Female ; Forensic Anthropology/methods* ; Humans ; Ilium/diagnostic imaging* ; Ischium/diagnostic imaging* ; Linear Models ; Male ; Pelvis/diagnostic imaging* ; Tomography, X-Ray Computed ; Young Adult

OBJECTIVE: To further improve the accuracy of bone age identification using the time of secondary ossification center appearance and epiphyseal fusion of 7 joints to estimate the age of living individuals. METHODS: DR films were taken from 7 parts including sternal end of clavical and the left side of shoulder, elbow, carpal, hip, knee and ankle joints of 1 709 individuals who came from eastern China, central China and southern China, whose ages were between 11.0 and 20.0 years. From those 7 joints 24 osteal loci were selected as bone age indexes, which could better reflect age growth of teenagers. The characteristics of secondary ossification center appearance and epiphyseal fusion were observed, and the mean and age range of secondary ossification center appearance and epiphyseal fusion were calculated. RESULTS: The fusion time of the 24 epiphyses were advanced at different degrees, the most obvious epiphyses the sternal end of clavicle, scapular acromial end, distal end of the radius, distal end of the ulna, iliac crest, ischial tuberosity, the upper and lower end of tibia and fibula. The appearance time of sternal end of clavicle, scapular acromial end, iliac crest and ischial tuberosity epiphyses were all found to be after the age of 12, and the female's age, approximately 1 year ahead of schedule in comparison with the male's. CONCLUSION The relevant forensic information and data for bone age identification should be updated every 10-15 years so as to provide accurate and objective evidence for court testimony, conviction and sentencing.
Adolescent ; Age Determination by Skeleton/methods* ; Asian People/ethnology* ; Bone Development/physiology* ; Bone and Bones/diagnostic imaging* ; Child ; China/ethnology* ; Clavicle/growth & development* ; Epiphyses/growth & development* ; Female ; Forensic Anthropology/methods* ; Humans ; Joints/growth & development* ; Male ; Sex Characteristics ; Tomography, X-Ray Computed ; Young Adult

Adolescent ; Child ; Epiphyses ; injuries ; Female ; Humans ; Male ; Manipulation, Orthopedic ; methods ; Radiography ; Radius Fractures ; diagnostic imaging ; therapy

OBJECTIVETo observe the clinical effects of miniaturized metacarpus steel plate for the treatment of child epiphysis injury, and to analyse its clinical advantages in the child epiphysis injury.

METHODSFrom June 2004 to May 2009, 85 children with epiphysis injury treated with miniaturized metacarpus steel plate included 52 boys and 33 girls with an average age of 6.6 years old ranging from 1 to 14 years. All the children suffered from just one part injury. There were 68 cases of upper limb injury, 19 of which were humerus epicondyle injury, 16 humerus head injury, 12 olecranon injury, 14 distal radius injury and 7 head of radius injury. The other 17 cases were lower limb injury, 12 of which were femur epicondyle injury and 5 tibia epicondyle injury.

RESULTSAll children obtained good intention,and no postoperative complications occurrenced. Eighty-one children were followed up for 6 months to 5 years (averaged 2.6 years). The results were evaluated at 4 weeks after the operation and showed that there were excellent in 44 cases, good in 21 cases, fair in 11 cases and poor in 9 cases.

CONCLUSIONTreatment of child epiphysis injury with miniaturized metacarpus steel plate can achieve perfect anatomical reduction in the early stage, protect the biological environment of the recovery. This treatment makes the postoperative joint functions and movements recovery nice, barely cause any bone malformation, and worth further clinical applications.

Adolescent ; Bone Plates ; Child ; Child, Preschool ; Epiphyses ; diagnostic imaging ; injuries ; surgery ; Female ; Follow-Up Studies ; Humans ; Infant ; Male ; Metacarpus ; Miniaturization ; methods ; Steel ; Tomography, X-Ray Computed ; Treatment Outcome

OBJECTIVE: According to the features of epiphyseal development of knee and ankle joints in male and female teenagers, the trend of epiphyseal development was analyzed and the possibility of its application in age estimation was discussed. METHODS: Firstly, radiographs of adem position were taken from both sides of knee and ankle joints from 1709 individuals from Eastern China, Central China, and Southern China (Age: 11-21 years old). Secondly, 5 osteal loci were selected as bone age markers from the two joints. Thirdly, characteristics of epiphyseal development were observed systematically and comprehensively. Fourthly, the proportions of "epiphyseal fusion" in different age groups were calculated, and confirmed the numbers of people which were included by epiphyseal fusion of knee and ankle joints. Finally, age range of each epiphyseal fusion was calculated by mathematical statistical analysis. RESULTS: Compared with the data of 1960s', the age of 5 epiphyseal fusions was earlier about 2-3 years. However, the results were basically the same as the recent studies. CONCLUSION The data on the time of epiphyseal fusion were updated. It is important to determine the accuracy in age estimation in male and female teenagers.
Adolescent ; Age Determination by Skeleton/methods* ; Ankle Joint/diagnostic imaging* ; Arthrography ; Bone Development/physiology* ; Child ; China/epidemiology* ; Epiphyses/diagnostic imaging* ; Female ; Forensic Anthropology/methods* ; Humans ; Knee Joint/diagnostic imaging* ; Male ; Young Adult

OBJECTIVE: To study the difference of Han female adolescent bone development in Henan and Zhejiang province. METHODS: All radiography including sternal end of clavicle and six main bone joints were taken from 599 female adolescents with age between 12 to 19 in Henan and Zhejiang province. Twenty four skeletal development indexes were analyzed based on "The Grading Standards" of skeletal growth of teenagers and then the bone age were calculated using mathematical model functions. The ratios of the bone age and the chronological age were analyzed by statistical software. RESULTS: The development of Henan female adolescents' skeleton was about 0.39 years earlier than that in Zhejiang at the age of 14-15 years old. The development of Henan female adolescents' skeleton was about 0.37 years later than that in Zhejiang at the age of 15-16 years old. The development of Henan female adolescents' skeleton was about 0.38 years later than that in Zhejiang at the age of 18-19 years old. There was no statistics significance in other age group. CONCLUSION The female adolescent bone development in Henan province is faster at earlier stage and then slower than that in Zhejiang province. The results provide potential value for the forensic medicine, anthropology and clinical medicine.
Adolescent ; Age Determination by Skeleton/methods* ; Age Factors ; Analysis of Variance ; Bone Development/physiology* ; Child ; China/ethnology* ; Clavicle/diagnostic imaging* ; Epiphyses/physiology* ; Female ; Forensic Anthropology/methods* ; Humans ; Joints/physiology* ; Models, Theoretical ; Sampling Studies ; Sternum/diagnostic imaging* ; Tomography Scanners, X-Ray Computed ; Young Adult

OBJECTIVE: To study the current development of hand-wrist bones of adolescents in China, and establish special forensic bony age standard for estimating 14 years of criminal responsible age in female adolescents. METHODS: One hundred and ten healthy girls aged from 13 years and 9 months to 14 years and 3 months in Lengshuijiang district of Hunan province were enrolled in this study. X-ray films of their left hand-wrists were taken dorsaventrally, and 15 sites on the wrist x-ray films were examined and measured under standard condition. The development grade was confirmed by maximal percentage to establish a method to estimate the bony age, which was then checked by single blind method. RESULTS: Development grade of the radius, the middle third phalanx and the fourth phalanx was partially closed (> 2/3), and the rest was wholly-closed with existence of the epiphyseal line. The development grade of the middle third phalanx and fourth phalanx was different between the younger group (< 14 years, partially closed, > 2/3) and the older group (> 14 years, mostly closed with existence of only epiphyseal line). The cross diameter of the osteoepiphysises were wider than that of all the diaphysises. The confirmed accuracy (in 30 girls) was 83.3%. CONCLUSION Our study seemes to be feasible in establishing the estimation standard for bony age determination. The standard established by developmental metaphysis and authropometry may be particularly helpful in forensic practice for estimation of accurate criminal responsible age in adolescents.
Adolescent ; Age Determination by Skeleton/methods* ; Epiphyses/diagnostic imaging* ; Female ; Forensic Anthropology/methods* ; Hand Bones/diagnostic imaging* ; Humans ; Radius/diagnostic imaging* ; Reference Standards ; Wrist/diagnostic imaging*