Reassessing Combat Helmet Protection Against Blunt and Blast Threats: A Structured Scoping Review

Area of Science:

• Military medicine
• Biomechanics
• Neurotrauma

Background:

• Traumatic brain injury (TBI) is a significant concern for military personnel.
• Modern combat helmets mitigate some injuries but their effectiveness against blunt trauma and blast-induced TBI is uncertain.

Purpose of the Study:

• To review combat helmet protection against TBI using biomechanical, medical, and operational evidence.
• To evaluate current helmet standards in relation to complex threat biomechanics.

Main Methods:

• Conducted a scoping literature review using SANRA framework.
• Searched PubMed, Scopus, and SciFinder for studies on combat helmets, trauma, and TBI.
• Synthesized data thematically by injury mechanism, protection metric, and helmet design.

Main Results:

• Helmets reduce skull fractures but offer limited protection against diffuse axonal injury and blast overpressure.
• Rotational acceleration, a key factor in mild TBI, is not in current standards.
• Helmet design elements like pad stiffness and coverage impact protection, creating trade-offs.

Conclusions:

• Existing helmet standards inadequately address complex biomechanical threats.
• Future helmet development requires multidimensional metrics, including rotational kinematics and strain thresholds.
• Balancing tactical functionality with neurobiological protection is crucial for advanced helmet design.