i think for ik handle...u will create only a ik . which u can control it.
but for ik spine handle , u create a ik handle, but also a curve. u control the ik with the curve, not the ik itself.
like u can animate the vertex or set up some cluster to play with it....
i'm still new la....dunno if this is right...but this is all i know
let some expert explain is better la hee
