EMPLOYEE WAS MOUNTING 31159 DOZER TO REPQIR IT, AS HE STEPPED FROM THE BLADE ARM SIDE STEP ONTO THE TOP STEP, HIS FOOT SLIPPED OFF THE LOWER STEP CAUSING HIS LEGS TO SEPARATE AND HE STTRAINED HIS RIGHT KNEE. HE WAS EVALUATED BY A DOCTOR ON 6/6/05 AND HAD AN MRI DONE, MRI RESULTS SHOWED A COMPLEX MENISCUS TEAR AND THIS STARTED HIS RESTRICTED DUTY