Despite the advantages of an additional level of modularity at the femoral neck there continues to be reports of clinical concerns of corrosion, metallosis and fracture of the modular neck in dual modular devices. The Stryker Rejuvenate, a dual modular hip implant, was voluntarily recalled in 2012 because of high revision rates. The authors of this study analyzed several Stryker Rejuvenate devices to determine why the implants failed. Patients in the study underwent relatively early revisions as all devices had been implanted for an average of 1 ½ years before being removed. Cobalt, chromium and titanium metal ion levels were measured and all were relatively low, despite metallosis and soft tissue destruction findings in many of the patients. In this study the most severe damage from corrosion was seen at the neck/stem interface, the area of greatest stress according to Finite Element Analysis. Finite element analysis is a computerized method that shows whether a product will break, wear out, or work the way it was designed. This study confirms what other studies have also found, that the area of most severe corrosion corresponds to the area that has the greatest stress, making the stem aspect of a modular neck/stem junction at increased risk of corrosion.
See Lanting, Brent et al. Correlation of Corrosion and Biomechanics in the Retrieval of a Single Modular Neck Total Hip Arthroplasty Design Modular Neck Total Hip Arthroplasty System, Journal of Arthroplasty, 30, 135-140
Weisman, Kennedy and Berris is currently serving on the leadership of national litigation involving DePuy’s ASR and Stryker’s Rejuvenate and ABGII devices. The firm has extensive experience in handling lawsuits against orthopedic device manufacturers and has been extremely successful in obtaining just compensation from clients from across the country for pain, suffering and lost wages resulting from failed implants. If you or someone you know has experienced such a failure, attorneys at Weisman Kennedy and Berris would be happy to answer any questions you might have about available rights.