PERSON WAS GETTING UP ONTO BOLTER FROM THE HEAD END OF BOLTER. HE HAD TO STEP UP 15"" FROM THE GROUND ONTO BOLTER PLATFORM, WHEN HE STEPPED UP HE HEARD A POP IN HIS RIGHT LEG BELOW THE KNEE. TH E AREA SWOLLED UP AND WAS PAINFUL. WENT TO HOSP AND X RAY SHOWED STRESS FRACTURE TO LEG.