What are the different types of AFO?

In short, there are primarily two different types of AFO's - Hinged, and Non Hinged or Solid AFO's.  The hinged type is used when the stability of the ankle is an issue but the muscle function is intact.  The Solid or Non Hinged AFO is used when there are varying degrees of muscle weakness or instability and the brace has to do all or part of the job the muscles are no longer able to do.