Journal de recherche médico-légale

Assessment of Age-related Adaptive Changes in Relative Transverse Dimensions of the Tibia and Fibula: A Preliminary Study towards a Different Approach for Age Prediction in Adults

Abstract

Fábio Rodrigues de Souza, Leandro Procópio Alves, Antonio Balbin Villaverde and Egberto Munin

Objectives: The study of transverse dimensions of long bones of the limbs provides valuable information of the human aging process and is of importance in forensic and anthropological sciences. The aim of the present study was to introduce a method to assess age-related adaptive changes in transverse dimensions of lower-limb bones employing a combined osteometric analysis as a different approach for age prediction in adults.

Material and methods: Twenty-four individuals (13 females and 11 males) aged from 22 to 65 years old were enrolled in the study. The mediolateral diameter of the tibia and fibula of the right leg at the one-third distal site was determined by conventional radiographs. An X-ray system model GE XR6000 (GE Hualun Medical Systems Co Ltd., Beijing, China) was used to obtain the radiographic images. Changes in bone dimensions were evaluated by regression and correlation analysis. The StatMate 2.0® software (GraphPad Software Inc., La Jolla, CA, USA) was used for the statistical analysis, with a significance level of 5% (p<0.05). Cohen’s d effect of size parameter was employed to estimate the effect of size on the statistical analysis.

Results: The plot of age as function of the ratio between tibial and fibular dimensions for the entire studied population showed a linear fit slope of (-24.1) year, p=0.0059, and r=0.55, indicating a linear relation of age with the tibia/fibula ratio of mediolateral diameters, regardless of the height or sex of the subject. Distribution analysis of the absolute values of the residuals (actual age-predicted age) gives a median of 7.9 years, with 6.1-10.6 years confidence interval at 95%.

Conclusion: The transverse fibular dimension serves as a normalization factor to compensate for different subjects height and sex when evaluating tibial morphometry. The preliminary data indicate that this method could be an alternative tool for predicting adult age in forensic matters.