text_1: Hip resurfacing aimed at boomers
text_2: The AP news story does a nice job of explaining what hip resurfacing is and how it fits into the history of hip replacement procedures. It summarizes the current availability of hip resurfacing in the US. However, the story provides virtually no evidence on the efficacy of resurfacing to support the mostly glowing testimonials of the three surgeons it quotes. According to the news article, the FDA “cited studies showing the Birmingham Hip resurfacer lasted at least five years…” What sorts of studies did the FDA analyze? What about the rest of the outcomes that patients value—such as improvements in pain and activity? Are there any randomized trials that compare similar patients who have undergone resurfacing with patients who have undergone total hip replacement? Is there follow-up beyond five years? These questions remain unanswered. The discussion of harms is likewise incomplete. The news article points out that hip resurfacing isn’t for everyone, and mentions two groups in whom it might not be appropriate. But the available research suggests the picture may be more complicated. There is disagreement about whether the procedure impairs the blood supply to bone or generates so much heat that it could cause the death of thigh bone. Bone death (necrosis of the femoral head) is a devastating complication for which there is currently no good solution. Other studies suggest additional potential problems. (For references and more details on potential harms, see “Harms of Treatment” above.) Although it is true that some researchers have found few problems with the devices and reported great success, readers deserve to know where the uncertainties lie. Perhaps the greatest uncertainty has to do with how long the implants will hold up. Though sufficient for FDA approval, survival of “at least five years” is not a strong endorsement. Total joint replacement, by comparison, has a track record extending 15 to 25 years. A closer look at the evidence might have reshaped the take-home message from this news report.