EE was standing on top step of lift pump, stepped backwards, foot slipped EE fell on right buttocks. No complaints, over time had discomfort, on 9/5 EE was seen in clinic & later seen by co. dr. EE had prior back problem, referred to specialist no restrictions that would limit duties. F/up visit w/specialist on 1/26/18 condition had not improved, EE was placed on modified duty.