the simplest I can break it down is that footwork is abstract, often atmospheric, and questionably danceable to anyone outside of Chicago, while juke is more uptempo and straightforward. they both share a lot of elements, like busy toms and looped utterances, but employ them in different ways.
this is probably suicide on a forum like this, but I'll make a loose comparison to halfstep-style dubstep and UK garage.. the former stripping away the pop sentiment and experimenting with subtle elements of the latter.