Quantitative biomechanical analysis of sharp force injuries to the head using finite element simulation

Area of Science:

• Biomechanics
• Forensic Science
• Computational Modeling

Background:

• Current sharp force injury assessment relies on subjective judgment, lacking objective data.
• Quantitative analysis is needed to determine applied force and injury severity in sharp force trauma.
• Finite element (FE) modeling offers a potential solution for objective biomechanical analysis.

Purpose of the Study:

• To construct and validate a high-fidelity FE head model for sharp force injury simulation.
• To investigate the relationship between momentum and head injury severity from sharp instrument stabs.
• To provide a quantitative biomechanical framework for forensic case analysis.

Main Methods:

• Reconstructed a high-fidelity FE head model based on the Total Human Model for Safety (THUMS).
• Validated the model using 3D-printed biomimetic skull experiments with a Chinese kitchen knife.
• Employed an erosion failure model for wound simulation and motion capture systems for data collection.

Main Results:

• FE model validation showed simulation and experimental results aligned within 15.0% error for wound dimensions and force.
• Minimum momentum required for penetrating injury in a homicide case reconstruction was determined to be 9.75 kg·m/s.
• Simulated momentum values correlated with injury severity: 0.75 kg·m/s (minor), 2.25 kg·m/s (moderate), and 5.25 kg·m/s (serious).

Conclusions:

• The study presents a validated biomechanical framework for quantitative simulation of sharp force injuries.
• The FE model provides objective data to enhance injury severity assessment in forensic investigations.
• This approach offers reproducible biomechanical support for case analysis and expert testimony.