If the animal jumps out of the vehicle, or the truck is in an accident, the animal could be injured. 
If the animal jumps out of the vehicle it will break its leg.
Just because the animal jumps out the vehicle doesn't mean it will break it's leg.
exists x1 x2 x3.(n_animal(x1) & n_animal(x1) & n_truck(x3) & n_vehicle(x2) & ((exists e1.(r_out(e1) & of(e1,x2) & Actor(e1,x1) & v_jump(e1)) | exists p1 x4.(in(x3,x4) & n_accident(x4))) -> exists e2 p2.(exists e3.(Theme(e3,x1) & v_injure(e3)) & Topic(e2,p2) & Actor(e2,x1) & v_could(e2))))
exists x1 x2 x3.(n_leg(x3) & of(x3,x2) & n_thing(x2) & n_thing(x2) & n_vehicle(x2) & n_animal(x1) & all e1.((r_out(e1) & of(e1,x2) & Actor(e1,x1) & v_jump(e1)) -> exists e2.(Theme(e2,x3) & Actor(e2,x2) & v_break(e2))))