Hip resurfacing: An alternative to hip replacement?

What can you tell me about hip resurfacing as an alternative to hip replacement? What are the pros and cons?

- Ken / Florida

Answer

Unlike traditional hip replacement, hip resurfacing doesn't require removing the "ball" of the hip (femoral head) and replacing it with a metal or ceramic ball. Instead, the damaged hip ball is reshaped and capped with a metal prosthesis. Resurfacing creates a bigger hip ball than is generally used in hip replacement, which may reduce the risk of dislocation. In addition, the damaged hip socket (acetabulum) is fitted with a metal prosthesis — similar to what is used in hip replacement.

Hip resurfacing first emerged as an alternative to hip replacement in the 1960s but fell out of favor because of problems with the polyethylene parts used at the time. A new generation of cobalt chrome caps and socket linings led to its re-emergence in the 1990s.

Although hip resurfacing has been used in Europe for many years, it is relatively new to the United States. The first hip replacement system was approved by the Food and Drug Administration in 2006.

Keep in mind that not everyone is a good candidate for hip resurfacing. Hip resurfacing is not recommended for people with osteoporosis — due to an increased risk of fracture of the femur.

In addition, there is some concern that the rubbing together of the metal parts used in hip resurfacing may produce very small metal particles that are absorbed into your bloodstream. The effect of these metal particles is unknown. However, a very small percentage of people may develop a metal allergy. Also, because these metal particles are eliminated by your kidneys, hip resurfacing is not recommended for people with impaired kidney function or diabetes.

More long-term research is needed to evaluate the potential risks and benefits of hip resurfacing. Some studies have raised concerns about a higher failure rate with resurfacing — which requires additional surgery. Although hip resurfacing may be attractive because it preserves more bone, this potential advantage must be weighed against the potential risks of additional surgeries.