| Popis: |
The signature weapon of the conflicts in Iraq and Afghanistan has been the roadside bomb (anti-vehicle mine, AV) or improvised explosive device (IED). Detonation of the explosive under a vehicle leads to rapid deflection of the vehicle floor, transmitting a very short duration, high amplitude load into the foot and ankle complex in contact with it. To date, there has been no clinical data on the pattern of lower limb injury or clinical outcome following an under-vehicle explosion. Using contemporary battlefield casualty data of UK service personnel injured in Iraq and Afghanistan, 63 casualties (89 injured limbs) were identified with lower leg injuries from explosion. Fifty percent of casualties sustained multi-segmental injuries to the foot and ankle complex and 29% required amputation, with 74% having on-going clinical problems at mean 33 months follow-up. Sub-group analysis showed that casualties standing at the time of explosion had significantly greater injury severity and poorer clinical outcome. In order to investigate the effect of limb orientation on injury severity, both finite element analysis and experimental approach was used. A traumatic injury simulator (Anti-vehicle mine underbelly blast injury simulator, AnUBIS) was developed to recreate the impulse witnessed in explosions within a laboratory setting. Initial experiments with instrumented cadaveric limbs impacted at 8.2-8.6 m/s demonstrated that for the same impulse the standing cadaveric limb sustained significantly severe injuries compared to the seated position. The data presented in this thesis has shown that lower limb injuries from AV mine explosions are associated with a poor clinical outcome. Primary prevention remains key in reducing the injury burden to the combat soldier. The development of realistic traumatic injury simulations allows for better understanding of the underlying injury mechanics, thereby focusing future research in injury mitigation and the development of improved lower limb test surrogates. |
