Pharmaceutical

Hip implant failure 29 percent higher in women, new study finds

hip replacement x ray Hip implant failure 29 percent higher in women, new study findsA new study of more than 35,100 patients who were surgically implanted with artificial hip devices reveals that women are much more likely than men to require revision surgery within the first three years to correct problems with the implant.

The research, published in JAMA Internal Medicine, was funded by the U.S. Food and Drug Administration (FDA) and comes amid a torrent of lawsuits against Johnson & Johnson and its orthopedic device unit DePuy alleging the company’s ASR all-metal hip devices caused serious, sometimes catastrophic, injuries in patients.

Of the 35,140 total hip anthroplasty (THA) patients studied, female subjects were 29 percent more likely than males to experience hip implant failure, regardless of size. The study’s sampling of THA patients encompassed 46 hospitals in the Kaiser Permanente Healthcare System.

After an average of just three years, 2.3 percent of female implant recipients experienced problems with their hip devices versus 1.9 percent of men. Hip failure problems included loosening and instability of the implant, broken bones, and infection.

“Females have a propensity to get smaller implants because just the size of their bones and the size of their structure,” orthopedic surgeon Dr. Monti Khatod told CBS News.

The study also showed that women who were implanted with metal-on-metal implants, such as DePuy’s ASR hip devices, had almost twice as many problems as men. Dr. Diana Zuckerman of the National Research Center for Women and Families told CBS News that this could be attributed to women being “more sensitive to the metals that are breaking off into the bloodstream.”

Metal hip implants consist of a metal ball that rotates inside a metal cup. Friction between the metal components releases particles of chromium and cobalt into the body, which may become ionized and can cause extensive damage and illness in some patients.

DePuy recalled its ASR hips in August 2010 as mounting evidence indicated high numbers of the devices were failing prematurely. Medical device registries in Australia and the U.K. were the first to pick up on the trend, but ASR devices were implanted in about 93,000 people before the recall.

Some medical professionals are calling on the FDA to require more testing of hip implant devices to determine which ones work best in women’s bodies and will last 15 to 20 years, CBS News reported.

Sources:

JAMA Internal Medicine
CBS News