Unfortunately, I don't think there is. League of Legends Updates about twice a month, which is undoubtedly going to cause some issues, both since the changes are frequent (though often not wholly drastic), and because we have a lot of questions on the subject.
The best bet is what we've had to make do with for Minecraft in the past (another problem, oft-updated, game) - keep an eye out for old questions, and if they're wrong, either suggest an edit (if the answer requires a small change), notify the author via comment (if you would rather not edit their answer, or don't know the details, other than that something changed), or post an up-to-date answer of your own.
If an update has removed the question entirely, the best bet is to flag it for mod attention as no longer relevant (we will close it as too localized, due to its historic content).