Integration of Muscle Pre-tension and Activation to Evaluate Neck Muscle Strain Injury Risk during Simulated Rear...

Area of Science:

• Biomechanics
• Injury Biomechanics
• Computational Modeling

Background:

• Preventing rear-impact neck injuries is difficult due to limited understanding of tissue-level responses and injury risks.
• Neck muscle injuries, often presenting as pain, are understudied, with a scarcity of data on their specific injury mechanisms.

Purpose of the Study:

• To investigate the impact of muscle pre-tension and activation on muscle strain and injury risk in low-severity rear impacts.
• To utilize a detailed finite element head and neck model (HNM) to simulate these effects.

Main Methods:

• A finite element head and neck model (HNM) was adapted from the GHBMC model and postured to match volunteer study data.
• Measured T1 kinematics were applied as boundary conditions, simulating three conditions: baseline, muscle pre-tension, and muscle pre-tension with activation.
• Calculated head/vertebral kinematics, muscle strains, and neck injury criteria to assess injury risk.

Main Results:

• The neck model exhibited an S-shaped curve followed by extension during rear impacts.
• Peak kinematics and muscle strains occurred later in the impact, during the extension phase.
• Muscle pre-tension and activation significantly influenced muscle strain magnitude and distribution, with highest strains at known injury sites.

Conclusions:

• Muscle pre-tension and activation are critical factors influencing neck muscle strain and injury risk in rear impacts.
• The developed HNM, incorporating muscle properties, serves as a valuable tool for assessing rear impact response.
• This model can inform the development of future injury mitigation strategies for neck injuries.