As readers to my blog will note, I am a licensed Texas medical doctor as well as a product liability attorney. We are currently fielding many phone calls from concerned hip replacement patients and the biggest concern for them is residual hip pain post procedure."Is that normal?" they ask. "How do we know if we are suffering from metallosis?" "My doctor is not concerned but I still feel that something is wrong?"
The answers to these questions remain elusive for several reasons. Firstly and foremost is the lack of research, disclosure and transparency from the hip manufacturers who knew or should have known about these problems and concerns.
Secondary, the orthopedic doctors, many of whom are implanting technicians, they do not have a firm grounding in internal medicine and because of their surgical training do not have the ability to diagnose and treat these types of conditions, short of re-do surgery. They drank the manufacturers kool-aid.
Diagnosis and treatment of metal on metal hip problem requires a multidisciplinary approach including the orthopedic, internal medicine and radiological specialties. Many orthopedic surgeons have reported that tissue surrounding a failed artificial hip looks like a biological dead zone. There are matted strands of tissue stained gray and black and large strips of muscle near the hip no longer contracted. Some patients with all-metal hips, ones in which the cup and ball of a joint are made of metal, said they had trouble finding a doctor to help them.
More than 10 years ago, some researchers had warned that the hips released metallic debris that caused potential health threats to patients. But those warnings were ignored, and now doctors and patients face a mounting public health problem as one of the biggest medical device failures surfaces.
All orthopedic implants, irrespective of their composition, shed debris as they wear, from the grinding action of joints. But researchers say they believe that the metallic particles released by some all-metal hips poses a special threat. This is because scavenger cells released by the body to neutralize the foreign debris convert it into biologically active metallic ions. In some patients, this sets off a chain reaction that can destroy tissue and muscle.
So far, only a small fraction of the estimated 500,000 people in this country who received an all-metal hip over the last decade have suffered injuries. But studies suggest that those numbers will grow and that tissue destruction is occurring silently in some patients who have no obvious symptoms like pain. And that is the crux of the problem, heavy metal blood tests can be normal and yet the hip joint is breaking down silently.
A recent study in England found that all-metal hips were failing early at three times the rate of hips made from metal-and-plastic components. This artificial hips are supposed to last 15 years or more. Most people recover well from a device replacement procedure, but specialists are also seeing growing numbers of patients with complications.
In the first six months of this year, the Food and Drug Administration received more than 5,000 reports about problems with the all-metal hips, according to a recent analysis by The New York Times.
In May, the Food and Drug Administration ordered makers of all-metal hips to develop studies to determine how frequently the devices were failing and the implications for patients. But those studies are not likely to be completed for years.
The final chapter has not yet been written on these metal on metal hips and so far DePuy has only recalled the ASR model. Johnson and Johnson, the parent of DePuy, continues to sell and market their Pinnacle metal on metal hip model.
