Forensic age estimation using Vieth classification in adolescents of northern China based on the knee MRI

To investigate the applicability of the Vieth classification and characteristics of ossification age in knee joint in adolescents of northern China. A retrospective study was conducted on a total of 1517 MRI images of knee joints from patients aged 10 to 20 years in the northern China. Vieth classification was used to assess the ossification age of distal femur and proximal tibia. Descriptive analysis was performed to obtain the maximum, minimum, median, and upper and lower quartiles of age at each stage, stack bar graph were used to show the age distribution at each stage. Mann-Whitney U test was utilized to analyze the differences in the stage of the proximal tibia and distal femur. Good intra-observer and inter-observer consistency (к = 0.89 and 0.88) was obtained. Regarding the distal femoral epiphysis, 100% of male participants in stage 3, 4(and 5) and 6 were over 12, 14 and 16 years old, respectively; 100% of female participants in stage 4, 5 and 6 were over 12, 14 and 16 years old. While for proximal tibial epiphysis, 100% of male participants in stage 4 and 5 were over 12 and 14 years old; 100% of female participants in stage 4 and 5 were over 12 years old. Ossification age of the proximal tibia mature earlier than distal femur (P < 0.001). Vieth classification can be used to infer the age of 12, 14 and 16 years in adolescents of northern China, providing a valuable reference for forensic age estimation.