EMPLOYEE WAS ON SPARE BOOM PART TRYING TO REMOVE A METAL TUBE WHEN THE TOOL BROKE/SLIPPED. EMPLOYEE LOST BALANCE/FOOTING AND FELL A DISTANCE OF ABOUT 4-6 FEET DOWN TO THE GROUND, LANDING ON LEFT ANKLE. ER X-RAY RESULTS OF A BROKE BONE ABOVE THE ANKLE, AND SOME SMALLER FRAGMENTS ALSO.