ON 6-21-04 AT 9:30 AM INJURED CALLED FROM THE DOCTORS OFFICE AND STATED THAT HE WAS NOT SURE WHEN HE JURT HIS BACK. HE THINKS THAT IT WAS WHEN HE WAS CHANGING THE HEAD WIPER ON THE 3A HEADER. HE SAID THAT HIS BACK WAS HURTING A LITTLE SAT (6-19-04) WHEN HE LEFT WORK, BUT HE DIDN'T THINK MUCH ABOUT IT. MONDAY HURTING WORSE. POSSIBLE PINCHED NERVE. MRI SCHEDULED.