Artificial hips under recall over joint ball
The ceramic may crack, the FDA said. But doctors might not know if patients have the affected hips.Sep 15, 2001 | AP
Hundreds of artificial hips are being recalled because one piece - the joint ball - is made of a ceramic that may suddenly crack.
It is the second major recall of artificial hips in the last year.
The Food and Drug Administration announced the recall yesterday, warning surgeons not to use the affected implants - and patients to call their doctors if they experience symptoms suggesting the joint has cracked.
The FDA has at least 14 reports of Americans in whom the recalled hips have broken.
Not all the recalled hips will break, and there is no need for more surgery unless one does. But there is no way to predict which hips will fracture.
Patients should "be aware this increased risk exists," FDA medical officer Dan Schultz said. "If they have any symptoms whatsoever, they need to get in to see their physician as quickly as possible. Don't assume . . . it's something that is just going to go away."
Symptoms include hip pain, a sensation of grinding or limitation of motion, Schultz said. The fracture sometimes is preceded by an audible pop.
The at-risk hips tend to break between 19 and 28 months after they're implanted, FDA compliance officer Carol Fedorchak said.
The French company St. Gobain Desmarquest recalled nine batches of its ceramic femoral heads - the ball portion of the hip implant - that were manufactured since early 1998.
The worst batch has an 8 percent breakage rate, well above the one-hundredth of one percent breakage rate expected for such parts, Fedorchak said. The other eight batches had a far lower breakage rate, but were being recalled as a precaution.
Apparently, a change in the manufacturing's heating process left the ceramic more fragile.
Eight U.S. makers of artificial hips use the French maker's ceramic part, and they are pulling affected implants out of surgeons' offices. The eight are: Apex Surgical of Lakeville, Mass.; Encore Orthopedics Inc. of Austin, Texas; Osteoimplant Technology Inc. of Hunt Valley, Md.; Smith & Newphew of Memphis; Stryker Howmedica Osteonics of Allendale, N.J.; and Biomet Inc., DePuy Orthopaedics Inc. and Zimmer Inc., all of Warsaw, Ind.
Patients likely will not know if they have a hip made with a ceramic femoral head; the joint part also can be made of metal. FDA officials said they did not require doctors to keep a registry of which artificial joints they had implanted in patients, but that patients could ask their surgeons if they kept such a record.
It's also unclear just how many artificial hips are affected. The French company recalled about 7,200 femoral heads, but not all were sold to U.S. hip makers.