An Alaska couple has filed a new Stryker hip lawsuit concerning the Accolade TMZF femoral stem with the LFIT V40 head against the hip implant manufacturer. A number of other plaintiffs have filed similar lawsuits claiming that the LFIT V40 is defective, and leads to premature loosening and painful disassociation.
The plaintiffs allege that the LFIT V40 was prone to fret and corrode and lead to hip implant failure. They filed the case in the U.S. District Court for the District of Alaska, and seek in excess of $75,000 in damages.
Stryker LFIT V40 Femoral Head Vulnerable to Corrosion and Loosening
The Stryker LFIT Anatomic CoCr Femoral Heads are used with a number of hip implant femoral stems, including the Accolade TMZF, Accolade 2, the Meridian, and the Citation.
In a hip implant system, the femoral stem goes into the thighbone, and the femoral head is attached to the stem. It contains the “ball” part of the hip socket, which fits inside the socket of the pelvis bone. This socket is usually covered and reinforced with an acetabular cup, so the femoral head goes inside this cup, where it rotates back and forth with movement.
The problem associated with the Stryker LFIT V40 femoral head is that it seems to be vulnerable to fretting and corrosion. It’s made of cobalt and chromium, as are other components of the hip system, and these materials rub against one another as the patient moves around. Over time, the rubbing can lead to a weakening of the metal. In some cases, this can cause the femoral head to disconnect and break off of the femoral stem, causing the hip joint to dislocate or disassociate.
Plaintiff Suffers from LFIT V40 Trunnionosis
According to the complaint, the plaintiff in this case went through a total hip replacement operation on March 24, 2008. The surgeon implanted an Accolade TMZF femoral stem with an LFIT V40 Head.
A few years later, doctors discovered a number of problems with the hip implant. First, a blood test revealed that the plaintiff’s blood level of cobalt was elevated. This was indicative of fretting and corrosion in the metal implant. Second, an MRI revealed the presence of a large soft tissue mass. When metal components rub against each other, they often shed small metal fragments into the surrounding joint and tissues, which can cause small pseudotumors or pockets of fluid.
The surgeon believed these problems were caused by corrosion at the junction between the Accolade TMZF and the LFIT V40 head, and he recommended revision surgery. The plaintiff underwent a revision surgery on January 13, 2015.
During the procedure, the surgeon found more problems. There was chronic inflammation in the joint, adverse tissue reactions, corrosion, and a condition called “trunnionosis.” This is a word used to describe the corrosion that occurs between the metal surfaces at the head-neck junction of the implant, and studies have found that this can to be a factor in causing pseudotumors and other hip implant problems.
After the surgeon removed the LFIT V40 head from the trunnion of the Accolade TMZF (the “trunnion” is the connection between the femoral head and stem), he found “extensive corrosion present at this site” and deterioration at the trunnion.
Indeed, similar to what happened in this case, in a 2016 study, researchers described nine cases of total implant failure related to metal wear and debris around the trunnion. In another 2016 study, researchers reported that trunnionosis was a growing cause of total hip replacement failure.
Stryker Recall Too Late for Plaintiff
In August 2016, Stryker recalled certain sizes of the LFIT V40TM femoral heads, because they had received higher than expected complaints of taper lock failure. The plaintiffs in this case claim that the recall was too late, and that the defendants failed to provide timely reports of the problems associated with these components. They assert negligence, defective design, manufacturing defect, and failure to warn claims.