A teenager was involved in a significant accident on the 4th of July.

What sort of accident could cause these injuries?  Hint:  it is not a motor vehicle collision, motorcycle accident or a fall.

This 13 y.o.  male was firingan anvil when it hit him.  The process of anvil firing requires that one anvil be placed upside-down on a firm surface, the space at the bottom of the anvil is filled with black powder and a fuse, and a second anvil is placed on top of the black powder.  The fuse is lit and the anvil can travel up to 100 ft in the air. 

In this case,  the anvil hit the boy in the chest and he arrested at the scene. His father who is a firefighter did CPR and there was return of spontaneous circulation.  The boy sustained severe injuries including a small intraparenchymal hemorrhage, bilateral pulmonary contusions with a mediastinal hematoma, an aortic valve injury, an open clavicle fracture, bilateral arm fractures and a finger fracture. 

Teaching point

Commotio cordis ( agitation of the heart)  is when a blow to the chest occurs during the vulnerable period of the heart on the T wave. It can trigger ventricular fibrillation.   It has been estimated that 50 joules is the amount need to cause fibrillation in the vulnerable period.  

When asked by the social worker in the Children's ED what happened, the father replied, " You wouldn't understand, it's a hill billy thing".  In truth, anvil firing has become a southern "sport" substituting for fireworks in some places.  The world championships of anvil firing are held in Missouri near Farmington, But the " sport" actually dates to the middle ages. when anvils were fired for St Clement's day; the patron saint of blacksmiths. 

References

Abrunzo RJ Commotio cordis. The single most common cause of traumatic death in youth baseball.  American Journal of Diseases of Children 1991145(11) 1279-82. Doi: 10.1001/archpedi. 1991.02160110071023 PMID 1951221.

Maron BJ, Estes NA “Commotio cordis”.  NEJM 2010 362(10) 917-27. Doi: 10.1056/NEJMra0910111 PMID 20220186.