EMPLOYEE WORKING WITH A SECOND EMPLOYEE ON A KILN TRUNNION WHEN USED A METAL BAR TO ROLL THE TRUNNION. WHEN THE TRUNNION MOVED OR BAR SLIPPED CAUSING THE EMPLOYEE TO LOSE BALANCE. EMPLOYEE STEPPED FORWARD TO REGAIN BALANCE, BUT STRAINED A MUSCLE. EMPLOYEE TREATED AT LOCAL CLINIC, PLACED ON RESTRICTIONS AND RETURNED TO WORK.