A plaintiff claiming injuries due to defective design of the Stryker LFIT V40 hip prosthesis has joined ongoing multidistrict litigation (MDL) against medical device manufacturer Howmedica Osteonics.

Plaintiff Annette M, is seeking damages for personal injury and economic loss, while her spouse, Charles, is claiming loss of consortium and services. Their lawsuit, filed in a federal court in Massachusetts, is one of many that have been brought against defendant Howmedica and its parent company, Stryker Medical, alleging that they knowingly manufactured and sold a product they knew was defective.

About the Stryker LFIT V40

The LFIT Anatomic V40 Femoral Head is only one of several Stryker and Howmedica products that are at the heart of current multidistrict litigation. It is the component that is attached to the top of the thigh bone (femur). The designation “LFIT” stands for “Low Friction Ion Treatment.”

The problem has been with the trunnion, or pivoting mechanism of the prosthesis. According to a study published in the Journal of Arthroplasty in September 2017, trunnion failure is rare in hip replacements. In the case of the LFIT however, the researchers estimated an average failure rate of 4.7 percent within approximately 16 months of implantation.

The Stryker LFIT V40 was approved by the FDA in July 2002 through the 510(k) Premarket Notification process. This means that the manufacturer was able to demonstrate that the device was “substantially equivalent” to an earlier device that had been given approval.

Critics say this process allows the newer, “equivalent” device to dodge proper testing. LFIT was subject to a Class 2 recall in August 2016, citing “secondary to taper lock failure.”

Other Stryker Hip Devices Have Failed

The LFIT V40 is not the only Stryker product to face a large amount of litigation. Another MDL in a federal court in Minnesota lists the Stryker Rejuvenate and ABG Hip implant as causes of action.

Specifically mentioned is the femoral head component, which is alleged to be defective. The master complaint notes that while most femoral heads consist of a single piece (“monolithic”), the Stryker products in question were made up two separate pieces (“modular”): the stem, which is implanted in the patient’s thigh bone, and the neck, which fits into the stem.

The former component is made from a proprietary titanium alloy, which is unique in the industry. The neck consists of cobalt and chromium.

Stryker has claimed that their design was stronger and less rigid than competing titanium hip devices. However, an independent scientific assessment published in 2016 found that the titanium alloy was prone to corrosion in the presence of bodily fluids.

Furthermore, the cobalt-chromium component is subject to fretting and corrosion where the head and stem come together. This results in microscopic bits of metal being released into the tissues, causing metal toxicity.

The Current Lawsuit

Annette states that she was implanted with a Stryker LFIT V40 femoral head on her right hip in November 2012. Under most circumstances, a prosthetic hip should last 20 years or longer; however, because of the complications resulting in her injuries, she was forced to undergo revision surgery to remove the device just over four years later.

Annette’s Stryker LFIT V40 is part of MDL No. 13-2441 (DWF/FLN), U.S. District Court, District of Minnesota.