Joint replacements can come loose and fail. Two reasons for this are infection and wear. Antibiotics mixed in with cement used to hold the implant in place have reduced the rate of infection.
Now, the most common cause of loosening is due to wear of the implant surfaces. Tiny bits of metal or plastic called debris flake off the implant. The bone around the implant starts to weaken. On an X-ray, it can look like there are holes in the bone around the implant.
At first doctors thought this problem was caused by the cement used to hold the implant in place. They called it cement disease. Today we know that the microscopic debris from joint replacements irritates the tissues around the implant. The result is a weakening of the bone. This condition is now called osteolysis.
Osteolysis (not cement disease) causes the implant to loosen over time. Movement of the implant inside the bone can cause hip and thigh pain and loss of hip motion. Research is ongoing to find a design for the implant that will stop the problem of osteolysis.