EE reported that he and co-workers were working pulling a conveyor motor off a CM when a piece of draw rock fell from between roof supports striking the top of his mine cap.Contacted mine after the end of the shift. EE was treated by a chiropractor on 8/19/09 after work.EE saw doctor on 11/10/09 due to continued headache/neck pain. EE began missing work on 11/12/09.