Starting in the late 1990s, hip implant product liability lawsuits have been filed against manufacturers of metal-on-metal orthopedic hip replacement implants. Over time with wear and tear, pieces of metal from the implants will shear off and contaminate the blood stream. This has lead to issues with problems for implant patients including revision surgeries. For the most part manufacturers have ceased producing metal-on-metal implants due to these dangers. In place of metal on metal implants, manufacturers have developed several new types of implants. These new implants are purportedly safer and more effective than metal on metal implants. It appears clear now from a new study that the traditional technology may be favorable.
The new study focused on three new types of hip replacement implants: ceramic-on-ceramic, modular femoral neck, and uncemented monoblock cups. Research was also done on two knee replacement technologies: high -lexion knee replacement and gender specific knee replacement. The research determined that none of the new implant technologies offers any new benefit or improvement over the previous technology. The new products do not improve functionality of the implants or patient reported outcomes. The researchers concluded that, “[w]e did not find convincing high quality evidence supporting the use of five substantial, well known, and already implemented device innovations in orthopedics. Moreover, existing devices may be safer to use in total hip or knee replacement. Improved regulation and professional society oversight are necessary to prevent patients from being further exposed to these and future innovations introduced without proper evidence of improved clinical efficacy and safety.”
The ceramic-on-ceramic implant bearing supposedly provides increased longevity and less wear with use. However, problems that have been reported with the implant include material fracture due to vulnerability to point loading, squeaking, audible component related noise, and liner chipping or canting. The modular femoral neck implant is purported to decrease dislocation, impingement and wear and allow better muscle balance. This product can result in fracture, dissociation, corrosion with metal ion generation, potential pseudo-tumor formation and component mismatch. The knee replacement high-flexion components were supposed to increase articular contact during high-flexion, improve stability and subluxation resistance, decrease stress on the quads, and reduce risk of knee cap impingement. It turns out that instead of increased stability, lower stability has been reported due to higher stress at the cement-implant interface. Increased edge loading and higher polyethelene wear and increased knee cap impingement have also been reported. The knee replacement technology is increasing risks for issues it was designed to remedy.
If you have been injured or have been forced to undergo revision surgery due to severe complications, contact Lambert Zainey today at 1-800-521-1750.