Hip Resurfacing Problems More Common Than With Hip Replacements

People undergoing hip resurfacing surgery may be more likely to experience problems and complications that lead to the need for revision surgery than those getting total hip replacement systems, according to the findings of new research.

In a study published online this week by the medical journal The Lancet, researchers found that hip resurfacing failure rates could be as much as six times higher than that of more traditional techniques, especially when smaller femoral heads are used. This has resulted in the conclusion that hip resurfacing should never be used with women.

Researchers working with the National Joint Registry for England and Wales used data from the registry to evaluate the rate of problems with hip resurfacing compared to hip replacement.

The data suggested that hip resurfacings fail quicker, except when large femoral heads were used with men, which had about the same failure rate as a total hip replacement. However, large femoral heads are only used in about 23% of all hip resurfacing procedures for men. Among women, researchers found that hip resurfacing problems result in failure within seven years for in about one out of nine cases.

While a hip replacement procedure involves replacing both the socket and femoral head with artificial pieces, hip resurfacing involves retaining the ball-like femoral head on the tip of the femur and grinds it down so that a cap can be placed on it.

While hip replacement systems can be made of a variety of substances, hip resurfacing systems are always metal-on-metal.

Large Femoral Heads Lead to More Revision Surgeries

The researchers used data from the registry from 2003 through 2011, involving 434,560 artificial hip recipients. They found that, in women, resurfacing led to a worse implant survival rate than hip replacement systems. For women age 55, the larger the femoral head the more likely there were to be hip resurfacing complications.

“We recommend that resurfacing is not undertaken in women and that preoperative measurement is used to assess suitability in men,” the researchers concluded. “Before further new implant technology is introduced we need to learn the lessons from resurfacing and metal-on-metal bearings.”

The registry has been a strict critic of metal-on-metal hip replacement and resurfacing systems, even calling for recipients to get annual blood tests to check for metal blood poisoning, or metallosis.

Many of the failed hip resurfacing and hip replacement systems that required revision surgery were found to have shed metallic debris into the body, raising levels of cobalt and chromium in the blood.

Problems with Metal-on-Metal Hip Replacements

In recent years concerns have surfaced about the safety of all metal-on-metal artificial hip systems, including all metal designs for total hip replacements.

In August 2010, Johnson & Johnson issued a DePuy ASR hip recall involving both their ASR XL Acetabular System implants and the DePy ASR Hip Resurfacing System, which was never approved in the United States. About 93,000 of the implants were sold worldwide before the manufacturer discovered that about 12% to 13% were failing within five years.

The use of metal-on-metal hip replacements has fallen sharply since the recall, with most experts concluding that they provide little or no benefit over other designs.

Johnson & Johnson now faces thousands of DePuy ASR hip lawsuits in the United States, alleging that they failed to adequately research the design or warn about the risk of hip replacement problems.

Similar product liability lawsuits have also been filed over other metal-on-metal implants, including the DePuy Pinnacle hip, Biomet M2A-Magnum hip and Wright Conserve hip.