Fillet between non planar splines or sketch lines

Hello All,

It is possible to create a fillet between a spline and a sketch line that are non planar? I want to make it flexible so I can change the angle the spiral finishes at and the legs still work.

Another way of doing it would be to create a plane on the end of the spiral in the plane leg bend. But I cant seem to do that either as it wont let me create a plane that goes through the first part of the leg, but is parallel with the axis of the spiral. 

I am trying to model a torque spring like the one below.

All help appreciated.

Thanks