The 26-year-old underwent an operation in 2008 and the joint has continued to give him problems since.
He told The Daily Telegraph: "This ankle, it is something that I have had problems with for years and years. Every day, I have to look after it. It's not 100%, but I just have to look after it. Playing all of these games in England is hard, so it is impossible, totally impossible, to be completely 100% all the time."
Silva added: "When I was at Valencia, I had an operation on it shortly after Euro 2008. For some reason, I always seem to get knocks and problems in the same area.
"But all you can do is try to be fit enough to play as often as possible. It is draining, but the important thing is to focus on the end of the season and winning the Premier League.
"After so many years as a professional footballer, you realise that it's all about the team."
Source: PA
Source: PA