Over-exertion in pulling or pushing objects
EE was moving a cement box with a forklift. The box was not picked up evenly with the forks. EE got out of the forklift & adjusted the box manually when he states that he felt a pop in his left arm. The box weighs an est. 500 lbs. EE did mention pain in his arm to fellow workers, however did not inform the safety staff till the next morning.