A General Kinematic Brain Injury Criterion Combining Translational and Rotational Effects

Area of Science:

• Biomechanics
• Neuroscience
• Computational modeling

Background:

• Human head impacts involve complex translational and rotational motions.
• Existing kinematic brain injury criteria often fail to adequately combine both motion types.
• This limitation can lead to significant misjudgments in assessing brain injury severity.

Purpose of the Study:

• To propose a General Injury Criterion (GIC) that comprehensively integrates translational and rotational head motions.
• To utilize maximum principal strain (MPS) as an intermediary variable for a more robust injury assessment.
• To develop a practical tool for rapid, kinematics-based brain injury evaluation.

Main Methods:

• 178 head impact cases were simulated using finite element models based on the THUMS model.
• Translational and rotational effects on MPS were quantitatively analyzed.
• The GIC was developed, compared with existing criteria, and validated against clinical TBI data.

Main Results:

• Translational and rotational motions have comparable contributions to MPS and require simultaneous consideration.
• The proposed GIC demonstrated the highest linear correlation with MPS among evaluated kinematic criteria.
• GIC achieved high classification accuracy for clinically diagnosed TBI cases (58-92%).

Conclusions:

• The GIC offers superior goodness of fit with MPS compared to existing kinematic criteria.
• The study validates the feasibility of GIC for predicting traumatic brain injury from impact kinematics.
• GIC serves as a valuable tool for bioengineering and safety engineering applications.