Revision total hip arthroplasty is becoming increasingly common due to the large number of primary total hip arthroplasties being performed annually. Failure of these arthroplasties has led to an increasing number of patients requiring revision arthroplasty. Various methods have been used to reconstruct the hip during a revision procedure. These have generally consisted of a cemented or uncemented femoral stem. It is now generally accepted that uncemented femoral stems have improved results over cemented stems, especially in those cases with compromised bone stock. There are two main alloys used for the femoral revision component, that is cobalt chrome and titanium. There may be certain advantages to the use of titanium, in particular, a reduction in future bone loss caused by stress shielding. Stress shielding is commonly seen with cobalt chrome implants. In order to assess this and the overall survival of these two different implants a randomized clinical trial is proposed.