I had a complete replacement socket and stem. After undergoing the replacement of my other hip it I have found out that the stem used in my left hip is two sizes larger in the shaft than the one in my right hip. I am ten weeks out with my left hip and almost pain free, the xrays show the shaft is touching bone in five different locations on the upper part whereas the right hip which is approaching three years is not touching bone anywhere in the upper stem. This cannot be referred to as loosening as it has never seated correctly. The surgeon that performed the second surgery commented that it must hurt like hell when I stand up to walk until the shaft is pushed back down, he said he is surprised I am able to walk as good as I do. The only good news is that he feels that as loose as the shaft is that he should be able to do a revision without splitting the bone to remove it. I am planning on the revision in December.