The DePuy ASR Acetabular System was introduced in 2005. It was designed to be longer lasting, more stable and provide increased mobility for younger patients with an active lifestyle. Like many hip replacement devices, the ASR Acetabular device did not undergo clinical testing as it was approved under the Food and Drug Administration’s (FDA) medical device exemption process known as the 510(k) Premarket notification clearance.
The 510(k) process allows device manufacturers to apply for approval for a product that is similar to an already approved device. Because of this exemption, the DePuy ASR Acetabular System had never been tested in humans before being marketed for public use, though DePuy claimed in information websites that the device “was thoroughly tested”.
By 2008, just three years after its approval, the FDA had already received over 300 severe adverse event reports regarding complications caused by the ASR hip system. DePuy issued a voluntary recall of all the ASR devices in 2010 but has not admitted fault. An internal review of the 510(k) process has uncovered flaws within the system and the agency was prompted to review the system, though no significant changes have yet taken place.
Design of ASR Acetabular Hip Replacement Device
Like many of the DePuy hip replacement products, the ASR Acetabular system was designed with metal-on-metal (MoM) construction. MoM devices were intended to be longer lasting and more stable, resulting in a decreased failure rate due to solid construction.
It was believed that MoM devices would not “wear out” as easily and would not shed plastic fragments into surrounding tissue as other devices did. The metal construction has turned out to be dangerous as well due to the chance that the metals will grate against one another and release metal fragments into surrounding tissue. The alloy used in the ASR devices is comprised of chromium, cobalt, and molybdenum which can be toxic to tissues.
In addition, many of the devices have failed due to dislocation and destabilization. Some experts believe that the Acetabular cup is too shallow and has caused some of the physical failures.
In 2007, a British orthopaedic surgeon presented information at a professional conference regarding his concern about failures but the company claimed that the high rate of complications was due to surgical technique. DePuy was also warned 7 times by the Australian health authority between 2007 and 2009 but due to the lack of communication between medical agencies from country to country, the information was not well-known.
In 2009, DePuy voluntarily pulled the ASR resurfacing from the Australian market but made no changes and continued to sell the device in the U.S. until a worldwide recall was issued in August of 2010. Information from a U.K. joint registry indicated that a large percentage of patients may experience failure of the device within 5 years, rather than the 15 years the devices were intended to last.
Side Effects of the ASR Acetabular System
Many of the problems caused by the ASR Acetabular device are a result of the MoM construction and the release of metallic debris into surrounding tissue. Other patients have experienced joint or device loosening and dislocation. Some of these side effects are severe and may be permanently disabling.
Symptoms of severe side effects include:
- Loosening of the device components resulting in instability and joint detachment
- Metal poisoning or metallosis due to the shedding of fragments or metal ions
- Necrosis or death and dissolution of bone and surrounding tissue
- Increased blood levels of cobalt and chromium due to absorption of metal ions
- Fracture of bones surrounding the implant
Patients may experience significant pain, inflammation and impaired mobility due to failure. Many patients have been required to undergo revision or reconstructive ssurgeries to replace the device and repair damage to bones caused by the devices. In many cases, the revision surgery is much more painful and requires a much longer recovery time and some patients have become permanently injured due to MoM devices such as the ASR Acetabular System.
DePuy ASR Acetabular Lawsuits
The DePuy company faces thousands of lawsuits in both state and federal lawsuits for injuries caused by the ASR Acetabular device. The first ASR lawsuit was filed in California and resulted in a 2013 $8.3 million judgment.
Over 90 thousand ASR devices were implanted worldwide and up to 40 percent of those devices may fail within the first five years after implantation. Over 10,000 lawsuits have been filed against DePuy for ASR Acetabular injuries. A multi-district litigation (MDL) was organized in the U.S. District Court for the Northern District of Ohio regarding more than 8,000 federal lawsuits but many more have been filed in state and local courts.
DePuy’s parent company, Johnson & Johnson has agreed to settle the federal cases for $2.5 billion and has begun payments but state and local suits have not been settled and many more are expected.
The DePuy Orthopaedics company is a division of Johnson & Johnson, the largest pharmaceutical and healthcare products company in the world. DePuy was the first orthopedics company in the U.S. and has over 200 surgical and medical device products, most of which have been successful. Unfortunately, three of the DePuy products have caused numerous medical injuries and resulted in hundreds of lawsuits – including the DePuy Pinnacle, ASR Hip Resurfacing, and ASR Acetabular System. The DePuy company has estimated annual revenue of $8 billion, while the parent company Johnson & Johnson has annual revenue of $72 billion.