Hip Replacement Found Safer for Women Than Resurfacing

Hip resurfacing, a procedure used as an alternative to hip replacement, is prone to early failure and shouldn’t be used in women, scientists found.

Women experience more problems than men in the seven years after surgery, U.K. researchers said today in a study published in the Lancet medical journal. Metal resurfacing implants fail more quickly than total hip replacements made of other materials, with the failure rate as much as five times higher for females, they said.

Resurfacing is more commonly offered to younger patients because it leaves more bone intact and can make it easier to perform a total hip replacement if needed later, according to the Mayo Clinic. The damaged hip ball is reshaped and capped with a metal prosthesis, as is the damaged hip socket.

“In view of these findings, we recommend that resurfacing procedures are not undertaken in women,” Ashley Blom, professor of orthopedic surgery at the University of Bristol’s School of Clinical Sciences in England and one of study authors, said in a statement.

The size of the patient’s femoral cap may make a difference, as about 23 percent of the men had large bones and experienced similar success rates to those who underwent total hip replacement, according to the study. Resurfacings of smaller femoral caps were prone to early failure, and women regardless of the femoral-cap size fared “much worse,” the researchers said.

Study Period

Researchers looked at National Joint Registry for England and Wales data on 434,650 hip operations performed from April 2003 through September 2011, of which 31,932 were resurfacings. The registry has the world’s largest joint-replacement database, with 1.2 million records covering hip, knee, ankle, elbow and shoulder procedures, according to the study authors.

In September 2011, the registry said the ASR Acetabular hip replacement, made by Johnson & Johnson’s (JNJ) DePuy Orthopaedics Inc., was removed or replaced 29 percent of the time after six years, compared with a 9.5 percent failure rate for all metal- on-metal implants. J&J issued a recall of the devices in 2010. The registry also found the metal-on-metal hip implants needed to be replaced more often than their counterparts.

“There might be a trade-off between higher occurrence of revision and better functional outcomes, which could be important for patients who are doing more physically demanding work or participate in sports,” Art Sedrakyan, a professor at Weill Cornell Medical College in New York, wrote in a comment accompanying the study. Women should be advised against resurfacing, he said.

To contact the reporter on this story: Allison Connolly in Frankfurt at aconnolly4@bloomberg.net

To contact the editor responsible for this story: Phil Serafino at pserafino@bloomberg.net