Age Estimation Based on a Radiographic Study of the Growing Foot

Abstract

Background: We sought to determine a predictive model of data, differentiated by sex, from a radiographic study of the skeleton of the foot as an alternative to the classic study of the hand. Methods: The study included 2,476 digital radiographs from 816 participants aged 0 to 21 years. The radiographs were from the Radiology Diagnostic Services of the Public Health System of Extremadura (Spain) from 2007 to 2011. The method used for their analysis consisted of assigning a numerical code to each ossification center of each growing bone of the foot and subsequently subjecting the data to a multivariate, decision tree, statistical analysis. Results: The decision tree study identified the bones that have a common age-dependent pattern of growth (as determined by a comparison of means test with P < .01) among individuals of the same sex. The quality of the decision tree predictions was evaluated in terms of the r2 coefficient. These values were r2 = 0.897 for females and r2 = 0.890 for males, thus establishing the predictive goodness of the model of bone data to provide a specific estimate of the individual's age. Conclusions: The foot is a good predictor of an individual's age from birth to complete bone maturity.