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Updated: Jan 24, 2026
07:28
Controlled Cervical Laceration Injury in Mice
Published on: May 9, 2013
17.1K
Passive cervical spine ligaments provide stability during head impacts.
Calvin Kuo1, Jodie Sheffels2, Michael Fanton1
11 Mechanical Engineering Department, Stanford University , 443 Via Ortega, Room 202, Stanford, CA 94305 , USA.
Journal of the Royal Society, Interface
|May 30, 2019
Summary
Neck muscles and ligaments stabilize the head during impacts. Ligaments become crucial during high-speed deceleration, limiting the benefits of muscle strengthening for head impact protection.
Area of Science:
- Biomechanics
- Musculoskeletal modeling
- Sports injury prevention
Background:
- Neck muscle strength and cocontraction may reduce head motion during impacts.
- Quantifying the roles of different neck tissues in head stabilization is essential for injury prevention.
Purpose of the Study:
- To quantify the relative angular impulse contributions of neck soft tissues to head stabilization during simulated head impacts.
- To investigate the influence of muscle activation state (relaxed vs. cocontracted) and impact type (experimental vs. football) on tissue contributions.
Main Methods:
- Utilized an OpenSim musculoskeletal model incorporating Hill-type muscles and rate-dependent ligaments.
- Simulated sagittal extension and lateral flexion head impacts under various conditions (relaxed/cocontracted muscles, experimental/football impacts).
- Estimated angular impulses from active muscle, passive muscle, and ligaments during impact acceleration and deceleration phases.
Main Results:
- During acceleration, active muscles contributed up to 30% of the impact angular impulse in experimental impacts with cocontraction, reduced to <20% in football impacts.
- During deceleration, active muscles provided 50% of the impact angular impulse in experimental impacts, but passive ligaments offered greater stabilization in football impacts.
- Ligaments demonstrated significant stiffening at high lengthening rates, outperforming active muscles in providing deceleration impulses during high-rate impacts.
Conclusions:
- Ligament properties, particularly their rate-dependent stiffening, play a critical role in head stabilization during high-rate impacts.
- The effectiveness of muscle strengthening or anticipatory muscle activation for head impact protection may be limited due to the dominant role of ligaments in deceleration.
- Understanding the differential contributions of muscles and ligaments is crucial for developing effective head protection strategies.
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