Ballistic shields are used by law enforcement personnel to manage crowd control and protect infrastructure. These shields are physically supported by a user’s arm to protect against projectile attacks or other weaponry. Although these shields are effective at stopping the projectile itself, a backward deflection of the shield may cause injury to areas along the upper extremity that are in contact with the shield. These kinds of injuries, caused by the rapid deformation of protective equipment from projectiles, can be severe. 

Researchers have wanted to determine how well these shields protect against upper extremity fractures.