EE WAS REMOVING A FEED TUBE FROM #1 MAGNET WHILE IN A SEATED POSITION AND USING A 24"" PIPE WRENCH. AS HE PULLED HE FELT A PAIN IN HIS BACK AND DOWN HIS RIGHT LEG. WORK COMP PHYSICIAN DIAGNOSED HIM AS HAVING MUSCLE STRAIN TO LOWER BACK. HE WAS GIVEN AN INJECTION, 2 PRESCRIPTIONSAND PLACED ON RESTRICTION AND NO LIFTING OVER 40 LBS.