The visceral response to underbody blast
Blast is the most common cause of injury and death in contemporary warfare. Blast injuries may be categorised based upon their mechanism with underbody blast describing the effect of an explosive device detonating underneath a vehicle. Torso injuries are highly lethal within this environment and yet their mechanism in response to underbody blast is poorly understood. This work seeks to understand the pattern and mechanism of these injuries and to link them to physical underbody blast loading
... dy blast loading parameters in order to enable mitigation and prevention of serious injury and death. An analysis of the United Kingdom Joint Theatre Trauma Registry for underbody blast events demonstrates that torso injury is a major cause of morbidity and mortality from such incidents. Mediastinal injury, including those trauma to the heart and thoracic great vessels is shown confer the greatest lethality within this complex environment. This work explores the need for a novel in vivo model of underbody loading in order to explore the mechanisms of severe torso injury and to define the relationship between the "dose" of underbody loading and resultant injury. The work includes the development of a new rig which causes underbody blast analogous vertical accelerations upon a seated rat model. Injuries causes by this loading to both the chest and abdomen can be best predicted by the examining the kinematic response of the torso to the loading. Axial compression of the torso, a previously undescribed injury metric is shown to be the best predictor of injury. The ability of these results to translate to a human model is explored in detail, with focus upon the biomechanical rationale; that torso organ injuries occur through both direct compression and shearing of tethering attachments. Survivability of underbody blast could be improved by applying these principles to the design and modification of seats, vehicles and posture.