http://www.copperjoint.com/how-to-get-back-the-lifestyle-you-had-before-the-chronic-knee-pain/

Knee injuries, in particular, can be rather challenging to come back from – we rarely pause to consider just how much is involved in how the knee joint system works, which is also how much can go wrong and how much functionality we can lose. As such, we rarely are able to completely grasp how to get each back into working form, and how to go from there.