Like many other metal-on-metal hip implant manufacturers, Wright Medical Technology has experienced problems with its Profemur and the Wright-Conserve Total Hip System, including metallosis and metal toxicity among recipients. Lawsuits regarding the Wright Conserve Total Hip System were consolidated on February 9, 2012 in an MDL before the Northern District of Georgia. Most of the plaintiffs’ claims in this MDL focus on the Conserve’s propensity to generate unacceptably high levels of cobalt and chromium leading to metallosis as well as the higher than normal risk of early loosening of the acetabular cup—total hip failure.
Risks of the Wright Conserve and Profemur Hip Implants
The Profemur Hip implant system implements a modular-neck stem which can be adapted to more fully accommodate the various leg lengths among patients. Unfortunately, that same feature can contribute to breakage, fracture, fretting and corrosion as well. Wright obtained FDA approval for their Conserve and Profemur designs through the 510(k) process which allowed them to market the implants without benefit of clinical trials and other safety testing procedures. Although the metal hip implants were designed to last much longer than their ceramic and polyethylene counterparts, in reality a high percentage of recipients have been forced to undergo risky surgical procedures to take out the defective device within only two to four years of the initial implant surgery.
While one of the greatest concerns that doctors face when implanting younger patients is to find an implant which can effectively withstand an active lifestyle, the all-metal hip implant designs have simply not lived up to that promise. The Australian National Joint Replacement Registry placed the revision rate of the Wright Profemur Hip Replacement at 11.2%--over twice the “normal” rate. Just like the recalled Stryker Rejuvenate and ABGII hip implants, the Conserve and Profemur’s modular-neck stems have the same risk of fretting and corrosion.
Corrosion Leading to Metallosis and Metal Toxicity
This means that the metal components react with body fluids, leading to corrosion. The corrosion, in turn, sends out microscopic metal ions into the body. These cobalt and chromium ions could lodge in surrounding tissues or enter into the bloodstream. When the metal shards burrow into surrounding hip tissues, inflammation will occur with tissue deterioration and death as well as bone loss possible. The patient will begin to experience chronic, and sometimes severe, pain and the implant could fail entirely should enough bone and tissue degradation occur. When the situation has advanced to this extreme level, there is little choice other than a potentially risky revision surgery for the implant recipient.
Should high levels of cobalt and chromium ions build up in the bloodstream, many symptoms of metal toxicity can occur including the following: Neurological issues such as memory loss, anxiety, depression and irritability, cardiovascular complaints, renal and hypothyroid issues, loss or deterioration of vision and hearing, skin disorders, pseudo-tumors and alterations in DNA. Those recipients of a Wright Conserve or Profemur hip implant should have the levels of cobalt and chromium in their bodies monitored on a regular basis. In addition, other tests ordered by your physician such as x-rays, bone scans or MRIs could be useful in determining whether your metal implant has caused you any adverse health reactions.