The Cochran Firm Legal Blog

DePuy Orthopedics is part of Johnson & Johnson and has been selling a metal hip replacement device called the ASR (Articular Surface Replacement). For about two years, DePuy has been receiving reports that this implant fails a few years after it has been implanted in the patient. While not widely used in the U.S., it is sold worldwide and many countries have been using it.

Dr. Stephen Graves is the director of an implant database in Australia and states that the ASR has been failing early far more often than competing devices. DePuy pulled the ASR from the Australian market in December of 2009. Late last year, DePuy announced that it would be phasing the ASR out by the end of 2010 because of sagging sales. This week, the company is issuing a warning to doctors that the ASR seems to have a high early failure rate for some patients.

Of DePuy’s planned phase-out and their current warning, Dr. Graves says, “It is way too late”. The ASR has been implanted in many thousands of people worldwide, many of whom have suffered intense pain because of its failure.

How Hip Replacements Work

The hip joint is a ball-and-socket joint where the rounded top of the femur (thigh bone) rotates in the acetabulum (a cavity in the pelvis). Synovial fluid within the joint prevents the bone surfaces from rubbing against each other, which is painful.

From age or injury, the two bone surfaces can be damaged so that they do not rotate smoothly. Hip replacement typically uses a plastic cup set into the acetabulum to provide a new surface for the femur to move against, and a metal knob for the top of the femur. A shaft is inserted into the bone’s interior to hold the knob in place.

The ASR uses a metal cup for the acetabulum instead of plastic, providing for what is known as a metal-on-metal hip replacement.

ASR for Hip Resurfacing as Well as Replacement

Some patients can have a hip resurfacing rather than a full hip replacement. Instead of replacing the femoral head, the doctor can attach a round cover to give it a new surface. The acetabulum is still given a metal or plastic cup.

The ASR system is used for hip resurfacing but the cup can also be used in a standard hip replacement, and this is the subject of DePuy’s current warning to doctors. In 2005, the FDA aproved the ASR cup for traditional hip replacements but did not put it through the usual clinical trials. Since 2008, FDA has received about 300 ASR complaints and in most of those cases, the patient had the ASR device replaced.

Whether there will be any defective product lawsuits over this ASR device remains to be seen. However, if you have been hurt by any type of defective product, you may want to contact us for a free case review, and learn whether you have a valid legal claim.

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