Emp was holding cage door on the bottom deck of #5 shaft mancage. Another emp was prying on the bottom of it to lift the door out of its hinges. The emp strained back when the door was dislodged from the hinges. Emp stated they did not want to see a dr at time of injury. On 3/28/2016 emp requested to see dr and was placed on restrictions for a strain to right shoulder.