Surgeons repaired loose cartilage in the Republic of Ireland defender's joint after an initial exploration revealed no serious damage.
And Foley told the Wanderers website: "I'd been struggling with the ankle on and off during last season and it was frustrating because I couldn't move as freely as I wanted.
"The last option was surgery, but it got to the stage where it was needed and the operation has gone well. So hopefully between four to eight weeks I should be back fit again."
Physio Steve Kemp said: "The surgery was carried out by a highly renowned surgeon who didn't find any surprises so it all went well.
"Kevin will be off his feet for a couple of weeks and we're probably looking at somewhere maybe six to eight weeks to be playing again."
Source: Team Talk
Source: Team Talk