Since the first hip replacement was performed in 1960, the operation has mushroomed. More than 285,000 total hip replacements are performed annually in the United States, according to the U.S. Agency for Healthcare Research and Quality.
The technology has evolved significantly, and not always successfully. Materials' issues have been blamed in some failures.
Some physicians are calling for a prohibition on artificial joints made of cobalt-chromium alloys in which the joint's metal ball rubs against its metal socket. Poorly designed or positioned metal-on-metal implants can lead to release of elevated cobalt-chromium ion levels into the blood. The result can be damaged organs and inflammation. Metal ions are also suspected carcinogens.