EMPLOYEE WAS ONE OF TWO EMPLOYEES CHANGING OUT A 50 HP MOTOR. THE EMPLOYEE WAS HELPING TO DRAG THE MOTOR INTO POSITION AND FELT A POP IN HIS BACK. THE INITIAL DIAGNOSIS ON 5-12-01 WAS A MUSCL E STRAIN. THE FOLLOW UP DIAGNOSIS ON 5-30-01 DEEMED PHYSICAL THERAPY NECESSARY FOR RECOVERY AND THUS DETERMINED AS A REPORTABLE INJURY.