Metal-on-Metal Hip Implants: Adverse Consequences

Many of our readers may recall that DePuy Orthopaedics, a subsidiary of Johnson & Johnson, voluntarily recalled two models of its hip replacement products in August of 2010 because of high failure rates. Since the recall of the DePuy ASR devices, approximately 5,000 lawsuits have been filed against DePuy Orthopaedics on behalf of individuals who were surgically implanted with the recalled DePuy ASR hips. Many of these individuals have had to undergo further surgery to have the recalled products removed and replaced.

These metal-on-metal hip prostheses began to grow in popularity in the early 2000s. Manufacturers claimed they have greater advantages and fewer limitations than the typical polyethylene-on-metal hip implants. One of DePuy’s biggest selling points was that the metal-on-metal devices had superior wear properties, meaning that they would last longer than the conventional devices and thus, have to be replaced less often. This led to greater use of the metal-on-metal devices, especially in younger individuals who were undergoing hip replacements. It has been estimated that as many as 500,000 individuals worldwide have all-metal hip prostheses. The DePuy ASR metal-on-metal devices were surgically implanted in 93,000 people worldwide between 2003 and 2010.

Studies have shown a significant number of metal-on-metal hip prostheses have failed due to accelerated wear of the articular surface (the metal ball and metal socket). Imagine rubbing two pieces of metal together for anywhere from 16 to 24 hours a day. Eventually, the metal surface begins to wear and debris is released. Likewise, accelerated wear of the metal ball and socket in an all-metal hip prosthesis causes metal debris to be released into the body’s soft tissue surrounding the hip joint. Eventually, the metal debris works its way into the bloodstream. Many of the individuals who were surgically implanted with the DePuy ASR hip replacement devices were found to have elevated levels of cobalt, chromium and other metals in their bloodstream, a condition known as metallosis.

Hundreds of thousands of patients may have been exposed to toxic chromium and cobalt particles as their metal-on-metal hip implants wear, according to a joint investigation by the British Medical Journal and BBC Newsnight. The all-metal implants, including the DePuy ASR and one model of the DePuy Pinnacle product, Smith & Nephew’s Birmingham hip and Zimmer’s Durom hip, release particles of their chromium-cobalt alloy as the metal ball and socket wear against each other, causing tissue and bone death and possibly exposing patients to an increased risk of developing some forms of cancer. There is still uncertainty about just how much metal in the bloodstream constitutes a health threat. It is increasingly apparent, however, that many patients with metal-on-metal hip implants showed blood levels of ions higher than normal. As a result of the heightened awareness of the potential adverse effects of increased levels of cobalt and chromium in the bloodstream, physicians and scientists around the world are conducting ongoing investigations to learn more about the long-term consequences of defective metal-on-metal hip replacement devices.

The FDA has decided to gather and review all available information about currently marketed metal-on-metal hip replacement systems, including information related to adverse events that may be associated with increased levels of cobalt and chromium in the bloodstream. In May of 2011, the FDA issued a statement and wrote to 21 manufacturers, informing them that it was invoking a rule requiring post-marketing studies in cases where a hip implant’s failure could have serious consequences. Among other things, companies would be expected to take blood samples from patients to measure metal ion levels.

Symptoms of hip implant failure can include pain, inflammation or swelling in the area of the hip implant, a clicking or grinding sound coming from the hip area, and difficulty walking. Any person who has had a hip replacement should contact his or her surgeon to determine whether they received a metal-on-metal hip replacement device. If your orthopedic surgeon does not have this information, you should be able to obtain the information from the hospital where the surgery was performed. You can contact the medical records department at the hospital where the surgery was performed, give them the approximate date of surgery, and request a copy of your “implant log” or “sticker log.” This is the record in your hospital medical chart that shows the manufacturer and model of the device that was surgically implanted in you.

The DePuy hip replacement lawyers at Suthers & Thompson are filing cases on behalf of individuals who were surgically implanted with metal-on-metal hip implants manufactured by DePuy Orthopaedics. The firm is presently representing 12 individuals in pending lawsuits. These lawsuits allege that the DePuy ASR hip replacement and the metal-on-metal Pinnacle hip replacement systems were designed defectively. Individuals who received a DePuy ASR hip implant or a metal-on-metal Pinnacle hip implant and have experienced pain in the hip or had to undergo hip revision surgery may be entitled to compensation for their medical expenses, lost wages, pain and suffering, and other injuries. For more information about filing a lawsuit involving a defective hip replacement product, contact an attorney at Suthers & Thompson toll free at 800-320-2384 or send an e-mail to jes@sutherslaw.com.