Traumatic amputation by explosive blast: pattern of injury in survivors.

Explosive blast causes a pattern of injury including primary blast lung, secondary fragment injury and traumatic amputation of limbs. Major traumatic amputation is rare in survivors of bomb blast but common in those who die. The mechanism of such injury has not been previously determined, but must be established if protective measures are to be developed for members of the armed forces. The nature of 41 traumatic amputations in 29 servicemen who survived to reach medical care after blast injury was investigated to determine the anatomical level of amputation and the pattern of soft tissue damage. Joints were an infrequent site of amputation and the tibial tuberosity was a particularly frequent site of lower-limb severance. Comparison of the pattern of injury was made with that seen in ejecting fast-jet pilots, who frequently suffer major flailing injury; there appears to be a substantially different injury distribution. The accepted mechanism of traumatic amputation, avulsion by the dynamic overpressure, is challenged; it is suggested that the shockwave resulting from an explosion is capable of causing at least bone disruption in a limb.