EE was walking, careful not to slip on wet ground(rain), and struck brim of hardhat on low pipe. Incident resulted in strained neck, but did not require medical attention at that time. EE's neck discomfort increased and bumped head on ladder on 07/01/07. EE had myelogram procedure on 08/14/07, which resulted in lost workday. EE has long history of neck/back pain.