Over-exertion in pulling or pushing objects
EE was removing the chock blocks from the haul truck. As EE pulled out the first block from under the tire EE felt a pain in neck and shoulder. EE was taken for medical treatment. The ground was frosty but the chock was not frozen in place. The chock is a 27 pound weight no defects. EE is on modified duties until the doctor releases EE back to full duties.