Vertical deceleration injuries.

Six patients simultaneously sustained vertical deceleration injuries. Vertical deceleration injuries are serious and characteristically involve major weight bearing structures with forces transmitted through the foot, leg, pelvis and vertebral column. Injuries of the lower extremity are likely to be unilateral and comminuted because the force of deceleration is applied to a small area. The severity of the injury increases by increasing the rate of deceleration and decreasing the distance through which the body is decelerated. More severe injury occurs when deceleration forces are applied to the body in the vertical axis compared with the transverse, provided that mass, velocity and stopping distance remain the same.