Just as use of a tire ultimately wears down the tread and leads to the need for a new tire or retread, the bearing surfaces-the moving surfaces that contact each other in a joint replacement-also wear down over time. A common question that is asked is “How long will this last?”

Fortunately, continued advances in bearing surface research have lead to longer life spans for joint replacement. There are a myriad of options in hip replacement bearing surfaces. Each has inherent advantages and potential disadvantages.

HWMPE “Plastic”-The most common material used in lining the acetabulum or “socket”, has the longest history of clinical use-over 40 years. This material has continuously evolved in its manufacturing process to reduce the rate of wear. Over the past seven years, “highly cross linked” HMWPE have been introduced and appear at this point to have lead to a dramatic reduction in wear. Early clinical data points to a nearly 75% reduction. Long-term data is not yet available. This reduction in wear allows surgeons to use larger femoral heads without compromising longevity and this reduces the risk of dislocation even further.

Ceramic bearing surfaces have been developed over the past twenty years. Their advantage is a smoother bearing surface than the standard cobalt-chrome femoral head. The disadvantage is the risk of cracking and failure through fracture. With evolutionary manufacturing and design, this risk is now extremely low.

Hard bearing (metal on metal or ceramic on ceramic) surfaces may create the lowest wear rates of all when compared to metal or ceramic on traditional HMWPE. The lifespan may be twenty years or longer with these surfaces.

I use all of these surfaces and choose the one that I feel is best suited to the individual patient based on their age, weight and activity level. Our goal is to choose a surface that allows the prosthesis to last as long as possible.