EE was rebuilding an off road truck box at Truck Shop. He was hammering a steel plate into place when he struck his elbow on the corner of the box. He just thought it was a bump/bruise. It was not until 4/26/2010 that this was reported as an injury. He went to doctor on 4/26/2010 where they drained the fluid buildup in his elbow and gave him a cortisone shot.