EE WAS WORKING WITH HIS CREW TO REPAIR THE MAIN CLINKER ELEVATOR. SOMETIME WHILE USING A 3-TON CHAIN HOIST. HE APPARENTLY STRAINED HIS UPPER BACK. BETWEEN THE SHOULDER BLADES. HE HAD BEEN REAC HING OVERHEAD AND PULLING HARD. THE INCIDENT OCCURRED ON 10-28-00. THE EE DID NOT SEE A DR UNTIL 11-6-00 AND MISSED HIS FIRST SHIFT OF WORK ON 11-8-00.