USA TODAY International Edition
Ills plague metal- on- metal hip implants
Patients report serious issues
Faulty hip joints implanted in tens of thousands of Americans pose adverse health effects in some patients even after removal, according to new research.
Doctors have known for several years that some hip devices, in which both the ball and cup are made of metal, were failing at faster rates than other hip implants. Research to be presented today at the annual meeting of the American Academy of Orthopaedic Surgeons in San Francisco shows that debilitating problems from all- metal implants can persist for years.
Last year, the Food and Drug Administration ordered 21 manufacturers to study patients who received metal- on- metal implants, after issuing a recall of one of the devices in 2010.
“This is a serious problem in the USA,” said Mathias Bostrom, an orthopedic surgeon at the Hospital for Special Surgery in New York City. “Some implants have a worse record than others, but almost all the metal- onmetal implants have issues.” He said that they were sometimes used in younger patients who wanted to remain active in sports.
Damage to the body occurs, Bostrom said, when the implant pieces move against each other and metal debris breaks off, lodging in nearby soft tissue and bone and entering the blood.
Inflammation and tissue death can occur around the joint, and problems affecting the heart and nervous system, although rare, can develop from toxins entering the blood, the FDA said.
In a 12- month period from 2005 to 2006, nearly 40,000 metal- on- metal hip replacements were performed in the USA, accounting for 32% of all hip replacements during that time, the American Society of Hip and Knee Surgeons said.
An estimated 500,000 people have them. About 285,000 hip replacements are performed a year, the Agency for Healthcare Research and Quality said. Although the group released a technology review in December saying metal- onmetal implants have higher revision rates than other implants, “the majority of patients who have them have had good results,” said Joshua Jacobs, chairman of orthopedic surgery at Rush Medical College in Chicago.
Many implants now are made of other components: metal and plastic, metal and ceramic, and all ceramic. Metal- on- metal implants designed to last 15 years were sometimes failing within several years. Their use has “decreased dramatically,” Jacobs said. “It’s important for anyone with a metal- on- metal implant to follow up with their orthopedic surgeon.” Signs of failure include pain, swelling or onset of a limp. Among other findings: u33% of patients in a study from the Netherlands ( 202 of 614) had adverse reactions in soft tissue. Authors recommend “close monitoring of all patients with metal- on- metal hips.”
A study from England found that 24% of patients who had revision surgery after a metal- on- metal implant had “worsening symptoms.” A third of those had more surgery. “Disease progression ( around the joint) was confirmed in all cases of re- revision,” the study said.
Orthopedic surgeon Douglas Padgett, of the Hospital for Special Surgery, said a study in which he was involved found 98% of the cups and 93% of the balls showed “moderate to severe scratching” in 46 retrieved metal-on-metal implants.