Juvenile Body Mass Estimation from the Femur Using Postmortem Computed Tomography Data

Area of Science:

• Forensic Anthropology
• Bioarchaeology
• Human Variation Studies

Background:

• Reconstructing the juvenile biological profile in forensic investigations typically focuses on age and sex.
• Body mass estimation, while not standard, is a valuable metric with historical interest in paleoanthropology.
• Existing methods for estimating juvenile body mass present an opportunity for forensic application.

Purpose of the Study:

• To evaluate the accuracy and precision of existing regression formulae for estimating juvenile body mass.
• To compare the effectiveness of different femoral measurements for body mass estimation.
• To identify limitations and potential biases in current juvenile body mass estimation techniques.

Main Methods:

• Utilized postmortem computed tomography (CT) scans from 94 individuals (birth to 12.5 years).
• Measured two specific femoral dimensions: distal metaphyseal breadth and cross-sectional polar moment of inertia (J).
• Applied previously published panel regression formulae to these measurements.

Main Results:

• Body mass estimation was more accurate using cross-sectional femoral measures compared to metaphyseal measures.
• All tested formulae consistently underestimated body weight.
• The degree of underestimation increased exponentially with the age of the juvenile.

Conclusions:

• Juvenile body mass estimation is complex and influenced by population-specific body composition variations.
• Current methods require refinement to account for ontogenetic changes and population diversity.
• Leveraging medical imaging data offers future potential for studying human variation across diverse developmental environments.