Age-specific comparison of some morphological parameters of the proximal phalanges of the hand in male children and adolescents from Tajikistan and Western India

Abstract

The aim of the study was (a) to establish ethnicity-specific differences in such morphological parameters of the proximal phalanges (PP) as the bone length and the width of diaphysis in male children and adolescents from Tajikistan and Western India and (b) to develop regression equations for determining their age based on the size of the PP. Materials and methods. Three hundred and sixty-two X-ray images of the right hand of male subjects were examined. All subjects originated from Tajikistan and Mumbai, India, and aged from 6 to 17 years. The relationship between the subjects’ age and the length of the PP (LPP) and the width of the diaphysis of the PP (WPP) was investigated using a simple linear regression and correlation analysis. The LPP and WPP dependence on age was determined using one-way ANOVA and the Kruskal–Wallis test followed by post-hoc analysis by age groups. Results. LPP and WPP of the subjects from Tajikistan and India correlated with age, with the correlation coefficient exceeding 0.5. In both ethnic groups, the correlation coefficients for LPP vs. age was greater than 0.8. The correlation coefficient for WPP vs age ranged from 0.68 to 0.77 in Tajiks and from 0.58 to 0.69 in Indians. Simple linear regression models were developed to predict the age from LPP ( R 2 > 0.6), except for LPP 5 for Tajiks. The LPP 5 values in Tajiks and the WPP values in both ethnic groups showed weak R 2 , which ranged from 0.35 to 0.53. Eleven significant differences were identified between the ethnic groups of the same age with respect to LPP and WPP. Conclusion . PP length was a better age predictor than the diaphysis width. The most reliable predictor for both ethnic groups was LPP 2. The PP parameters did not change uniformly over time. The PP demonstrated especially intensive growth between 12 and 15 years. The most significant differences in LPP and WPP between two ethnic groups were found for the ages of 8 and 15–16 years, with LPP and WPP in Tajiks exceeding those in Indians.