The federal government received a surge in complaints in recent months about failed hip replacements, suggesting that serious problems persist with some types of artificial hips even as researchers scramble to evaluate the health dangers, according to an article found at The New York Times.
An analysis of federal data by The Times indicates that the Food and Drug Administration (FDA) received more than 5,000 reports since January about several widely used devices known as metal-on-metal hips, more than the agency had received about those devices in the previous four years combined.
The vast majority of filings appear to reflect patients who had an all-metal hip removed, or will soon undergo such a procedure because a device failed after only a few years; typically, replacement hips last 15 years or more.
The mounting complaints confirm what many experts have feared — that all-metal replacement hips are on slippery slope to become the biggest and most costly medical implant problem since Medtronic recalled a widely used heart device component in 2007.
Though immediate problems with the hip implants are not life-threatening, some patients have suffered crippling injuries caused by tiny particles of cobalt and chromium that the metal devices shed as they wear.
Hip replacement is one of the most common procedures in the United States and, until a recent sharp decline, all-metal implants — one in which both the artificial ball and cup are made of metal — accounted for nearly one-third of the estimated 250,000 replacements performed each year. According to one estimate, some 500,000 patients have received an all-metal replacement hip.
One of the most problematic devices, the A.S.R., or Articular Surface Replacement, was recalled last year by Johnson & Johnson and accounted for 75 percent of the complaints reviewed by The Times. A precise count of failed implants reported to the F.D.A. is hard to come by because of the agency’s overlapping reporting system, though The Times sought to eliminate duplicate reports about the same incident. Some complaints came from outside the United States.
Under FDA rules, many all-metal devices were sold without testing in patients or without a requirement that producers track their performance. But in an unusual intervention, the FDA in May ordered producers to study how frequently the devices were failing and to examine the threat to patients. Now, researchers say, producers face substantial hurdles in recruiting the hundreds of patients needed to conduct sound studies because of the lack of patient registries.
“They are grasping at how they are going to get this information,” said Dr. Robert S. Namba, an orthopedic surgeon with Kaiser Permanente.
In addition, researchers are struggling to understand the tissue damage caused by the metallic debris. While some patients experience pain, other patients with the same damage have no pain, complicating decisions about whether to remove devices.
As problems and questions grow, most surgeons are abandoning the all-metal hips, saying they are unwilling to expose new patients to potential dangers when safer alternatives — mainly replacements that combine metal and plastic components — are available.
Dr. William Maisel, the chief scientist of the FDA. division that oversees medical devices, said he believed that producers would mount rigorous studies and find answers. But he acknowledged that it could take several years.
“There is not an existing infrastructure for studying this kind of information,” Dr. Maisel said.