Cementless Joint Prostheses: Advantages and Disadvantages
A cementless prosthesis, also called a press-fit prosthesis, has a rough surface or porous coating that encourages the natural bone to grow onto it. New bone growth will span only 1 or 2 mm, so the surgeon must use special tools to shape the natural bone to fit snugly with the prosthesis.
A number of surgeons prefer cementless components because:
They believe cementless components offer a better long-term bond between the prostheses and bones.
Cementless components eliminate worry about the potential breakdown of cement.
The downsides to cementless prostheses are that:
Press-fit prostheses require healthy bones. Patients with low bone density due to osteoporosis may not be eligible for these components.
It can take up to three months for bone material to grow into a new joint component.1,2
Because it takes time for the natural bone to fully adhere to the new joint components, experts debate whether or not patients should postpone putting their full weight on new joints.
Peter..I would check you had a cement less fit as the edit says it takes nine to ten weeks for bone material to form over the new joint, you do not walk on cement less joint for several months ( that is to say put body weight on the new Prostheses), this is the problem with that type of fitting, but as no cement is used it does not over time deteriorate, so it can last a lot longer (we hope)
Either way mine is now nearly ten years since my total hip replacement, never looked back, no pain at all from the minute I woke up after the Op! best thing I did so much pain before..good luck to you and anyone contemplating this operation, go for it!
Jim...

also edit..from the Net.
How Soon Can A Patient Walk on a Cementless Hip or Knee Prosthesis?Patients may be advised to avoid full weight-bearing on cementless components during the first 4 to 12 weeks after surgery. Limited partial weight-bearing is allowed. This cautious approach lengthens a patient's rehabilitation schedule but guards against stressing or loosening a new joint, which can be painful and require a second surgery.
Hip Replacement Surgery Video
Hip Replacement Surgery
Alternatively, other patients may be told to begin putting full body weight on the new joints just a day or two after surgery.3 Studies of cementless hip replacements support this approach, showing that well-fitted cementless hip prostheses can handle the pressure.3-6 Full weight-bearing during early recovery and rehabilitation promotes healthy muscle and bone tissue and lowers the risk of post-surgical deep vein thrombosis (DVT).
Research in this area is ongoing. For now, surgeons must base their rehabilitation recommendations on many factors, such as the joint being replaced, the specific component being used, the patient's physiology, and past experience. Patients who are concerned with this