Mathematical models for teenager's living age evaluation based on CT image of medial clavicular epiphysis

To explore the correlation between volume rendering (VR) statistics of medial clavicular epiphysis and living age, and establish the mathematical models for living age evaluation using the CT image of medial clavicular epiphysis based on the growth rules of osteoepiphysis of medial clavicle.

The CT images of the medial clavicles from 795 teenagers aged 15-25, 387 males and 408 females, were collected in East and South China. VR 3D images were reconstructed from 0.60 mm-thick slice CT images. The epiphyseal diameter, sternal end diameter, and their respective diameter ratio (the left: X1; the right: x3); epiphyseal area, sternal end area, and their respective area ratio (the left: x2; the right: x4), were measured and calculated. All these observations were analyzed using SPSS 19.0 statistical software. The statistical differences in gender and age were analyzed by Mann-Whitney U test. The mathematical models were established using least square. Sixty trained subjects, 30 males and 30 females, were tested to verify the accuracy of the established mathematical models.

In the group of same age, x1 showed significant difference in gender; the same results were observed in x2, x3, and x4, which suggested that the growth rules of osteoepiphysis of medial clavicle were highly correlated with living age. The accuracy of these mathematical models were all above 67.6% (+/- 1.0 year) and 78.5% (+/- 1.5 year).

The mathematical models with reasonable accuracy could be manageable in practice to confirm the conclusion of the atlas method. The current study can contribute to the single skeletal age evaluation.