EE WAS CHANGING FILTER SECTORS ON 5D FILTER. AFTER REMOVING A SECTOR FROM DISC #3, HE ROTATED TO HIS RIGHT WITH THE SECTOR. WHILE ROTATING THE METATARSAL GUARD ON HIS LEFT BOOT CAUGHT IN THE F LOOR GRATING. HIS BODY CONTINUED MOVING BUT HIS FOOT DID NOT, RESULTING IN A STRAIN TO HIS KNEE. EVALUATED BY A PHYSICIAN, KNEE IMMOBILIZER WAS ORDERED.