Device’s Mixed Metals May Be to Blame
Medical device maker, the Stryker Corporation, is based in the United States and sells medical devices worldwide. Now, Stryker faces litigation in Boston, Massachusetts and New Jersey over its LFIT Anatomic CoCr V40 Femoral Head (Cobalt Chromium V40). To date, there are a total of 230 cases pending in the two litigations.
Allegations include that the metal-on-metal ball and joint hip implant system fails prematurely because of an alleged design defect. The femoral head and femoral stem are a modular connection; the stems are generally constructed with titanium alloys; the heads are constructed of cobalt chromium. The current litigation involves cobalt chromium heads combined with titanium stems. Apparently, the mixed metal construction may fret and corrode over time with the repeated motion of the hip when walking, arising, and sitting. The various metals meet at the junction and lead to failure after about six to eight years and are more common when larger femoral heads are used. Larger heads tend to be approximately 36 millimeters in size; however, smaller heads are known to fail, as well.
Initial symptoms of device failure include pain in the hip area. Extensive corrosion may lead to the implant cracking. When a Stryker LFIT Anatomic CoCr V40 corrodes, elevated cobalt levels are typically seen. Elevated chromium levels may also be seen as well as tissue or bone damage, pseudotumors, and fluid. In some cases, patients suffer from what is known as disassociation, the worst complication seen in this device in which the femoral head cracks off as the trunnion (pivot point) becomes so corroded it falls out of the stem. In every case a revision surgery is required to remove the disconnected dissociated head and the femoral stem. It is possible that patients implanted with Cobalt Chromium V40 implants may have corroding junctions but do not experience pain.
The taper lock portion of the component that connects the femoral head to the femoral neck may weaken or completely break, which may lead to catastrophic hip implant failure. Patients may suffer from broken bones, dislocation, joint instability, loss of mobility, increased metallic debris and metallosis (metal poisoning), and severe pain. In addition to dissociation of the femoral head from the hip stem, taper lock failure may also lead to fractured hip stem trunnion, insufficient range of movement and soft tissue tension, noise emanating from the implant, loss of the implant, minimized bone fixation strength, increased wear debris, and implant construct with a shortened neck length. Taper lock failure symptoms may include adverse total tissue reaction, broken bones in the area of the component, dislocation, inflammation, joint instability, leg length discrepancy, loss of mobility, the need for revision surgery, and significant pain. Failure signs include unexpected pain, limited mobility, and/or loss of range of motion.
In a total hip replacement, there is generally a femoral component that replaces the femur (thigh bone). The femoral component is made up of several parts such as a stem that is inserted into the bone and a ball (head) that sits on top. The ball and stem are joined at the femoral neck (a taper lock system). The femoral ball connects to the acetabular component, a cup that replaces the hip socket and to copy the hip joint’s natural motion.
Patients must typically undergo revision surgery to explant the defective device and undergo implantation with a different device when these injuries occurs.
Parker Waichman LLP, a nationwide personal injury law firm, notes that metal-on-metal hip implants have come under increasing scrutiny following recalls and thousands of lawsuits. The firm represents numerous clients in metal-on-metal hip implant lawsuits and continues to offer free legal consultations to individuals who have questions about filing a Stryker LFIT CoCr V40 Femoral Head lawsuit.
Cobalt Chromium V40 Implant Background
Previously, Stryker recalled certain lots of its femoral heads. The components involved were manufactured prior to March 2011 and were recalled due to higher than expected complaints concerning failure of the femoral head to fully lock onto the stem at the stem-head taper junction, known as “taper lock failure.” Stryker recalled approximately 40,000 Cobalt Chromium V40 implants; hundreds of thousands of these implants have been sold. Meanwhile, failures have been seen with these devices in clients implanted after the recall.
Various studies have been released in recent years that tie elevated cobalt levels from metal-on-metal hip implant devices with brain dysfunction. In Great Britain, the Medicines and Healthcare Products Regulatory Agency (MHRA) is calling for additional research following numerous scientific investigations raising the issue of high cobalt levels and brain dysfunction.
A 2016 study determined that nine cases of total hip implant failure were associated with metal wear debris in this area of the implant. The patients also suffered from abnormal levels of cobalt and chromium blood levels, tissue damage, and hip implant failure. Each of the patients underwent revision surgery to repair the allegedly defective implant. Revision surgery generally involves removing and replacing the allegedly defective device. This is a more painful, costlier, riskier, and complex surgical process than the original surgery and is also associated with longer recovery times and hospital stays as well as intense and longer physical therapy. Sometimes, insurers do not cover revision surgeries.
Some hip implant components are created from metal alloys and not more traditional materials such as ceramic. Metal-on-metal implants were thought to extend the life of traditional hip implants, expanding the market to a growing population base that is younger and more active and comprised of individuals who are looking for a stronger, longer lasting implant.
Metal-on-metal implants and other newer designs were also allowed to be released to the market with minimal testing through the U.S. Food and Drug Administration’s (FDA) 510(k) clearance protocol, have proven to be problematic.
Meanwhile, Stryker has also been sued over its metal-on-metal ABG II and Rejuvenate hip implant medical device products, which were recalled in 2012 over risks of fretting and corrosion. The company recently expanded its $1.4 billion settlement for these lawsuits to include plaintiffs who underwent revision surgery prior to December 19, 2016.
Filing Defective Medical Device Lawsuit
If you or someone you know suffered injuries related to the use of defective medical device or device component, including metal-on-metal hip replacement and other hip devices, you may have valuable legal rights. Our personal injury lawyers offer free, no-obligation case evaluations. For more information, please call 1-800-YOURLAWYER (1-800-968-7529).