More Viewpoints on Metal-on-Metal Hips
April 1, 2012 | Evaluations & Guidance
The use of metal-on-metal total hip prostheses has plummeted in the last few years. As discussed in our January 2012 Guidance Article on hip implant designs and materials, major concerns have emerged about their use. Chief among these are evidence of the harmful effects of metal ions released from these implants, evidence of high revision rates, recalls of two implant models sold by DePuy Orthopaedics, and recent FDA requirements for postmarket surveillance of all metal-on-metal implants. Concerned about patient safety and liability, some surgeons have abandoned metal-on-metal designs. However, some observers question whether all metal-on-metal implants should be automatically written off. ECRI Institute spoke with two orthopedic surgeons and reported their perspectives in an article in the February 2012 issue of its Health Technology Trendsnewsletter.
Michael E. Berend, MD, orthopedic surgeon at Franciscan St. Francis Health’s Center for Hip and Knee Surgery (Mooresville, Indiana), says that the bad press has resulted in a tendency to lump all metal-on-metal implants together, despite the fact that, as he put it, “There are significant differences in manufacturing, in tolerances, in design . . . in the components, and in the way they’re implanted.” In other words, “Not all metal-on-metal implants are created equal.” Berend also pointed out that metal-on-metal designs have certain advantages over other materials. For instance, larger femoral heads can be used, which reduces postoperative dislocation rates. Berend added that his facility has had an excellent early track record with metal-on-metal hips—specifically, the Biomet Orthopedics M2a-Magnum—and has implanted more than 1,200 of these prostheses.1 Notably, however, Berend said, “We have changed the use of the...