On 3/9/21 employee was on a bolter when the sound windshield moved contacting hardhat jarring head and neck. Was seen at ER, CT scan done, & full release issued. Returned to work 1st shift back 3/16/21 & on 3/17/21 they informed the company they had seen their own doctor & taken off work for four weeks to do physical therapy making this reportable on 3/17/21.