I had a problem with my ankle very early on when i was about 11 or 12 was only fractured. However was always weaker than my other after that so playing football i used to wear a support alot, which in itself was bad as you become dependant upon it.
Took me a while to start playing without one again and had various niggling injuries on the same ankle afterwards. Funnily enough i think now thats it had a few years of rest and not constant impact on it from sport its actually alot better.
Im sure arsenal will do their very best to help rehabilitate eduardo though.