Revising a hip replacement – what are the challenges?

I see a lot of patients who are relatively young and unfortunately need a hip replacement because the hip has become damaged and painful due to osteoarthritis. If you are young at the time of your hip replacement an obvious question is how long will it last and what will happen when it wears out? Can it be re-done and will it be as good as new?

Traditionally we have considered 15-20 years to be a rough length of time for a hip replacement to last. The cause of loosening tends to be the bearing surface, ie. The parts that move against each other; the ball head on the top of the femur and the liner of the new hip socket. Overtime the surface material rubs away getting thinner and thinner with small particles released into the soft tissue produce an inflammatory reaction which slowly causes bone to melt away from the interface with the hip implant. The bone can end up very weakened as a result of this process and this is where the problem lies when we have to do a revision operation; we have to put a new implant into a very compromised bone which may not easily lend itself to having something mechanically fixed to it again. Imagine a crumbling wall with raw plugs not able to gain much purchase!

The best scenario is never to get into that situation in the first place. If the bone remains in good condition around a hip replacement and the replacement itself shows signs of wear, it is actually relatively straightforward to do a revision procedure with a very good chance that the hip will again last a long time.

Newer materials are showing signs that they have better wear properties and the particles released cause less adverse reaction in the surrounding bone and soft tissues. Ceramic articulating with ceramic has the lowest wear rate of the available bearing couples and the particles are very inert so the bone remains in good condition and is not compromised should future surgery be necessary. For these reasons I see this option as being the optimal choice of the bearing surfaces that we have available today.