May 2, 2013

What You Should Know About the Recalled Stryker ABG II and Rejuvenate Hip Implant Devices Part One


This is part one of a two-part article regarding the issues surrounding the Stryker Rejuvenate and ABG II hip implant devices. Due to the recent number of defective metal-on-metal hip implants such as DePuy’s ASR, many surgeons placed their trust in a new design introduced by Stryker in 2008 and 2009. The all-metal implants place a cobalt and chromium ball inside a cobalt and chromium acetabular cup; those components rub against one another causing microscopic metal ions to shear away, burrowing into the hip tissue or entering into the bloodstream. 

Stryker’s new design used a ceramic ball with a metal neck juncture as well as small metal trunnions located on either end of the neck piece. The design also boasted four component pieces rather than the usual two which allowed surgeons to choose the individual components based on their patient’s size and level of activity. Surgeons were finally able to custom-fit a hip implant device, using the best angles and lengths for their patients.

Relatively soon after the two Stryker implants were marketed and began being implanted, adverse reports began coming in from patients and the design which was once believed to be the greatest innovation in hip implants found itself issuing a recall in July, 2012. By the time 53,000 Rejuvenate and ABG II implants had been marketed and the majority implanted the recall was issued, stating the risk of fretting and corrosion as well as early failure. Stryker patients were suffering from pain, inflammation and symptoms of metal toxicity. When the neck juncture suffers corrosion toxic metal particles can cause metal toxicity with such symptoms as:

·         Neurological problems
·         Cardiovascular issues
·         Renal and thyroid disorders
·         Loss of vision and hearing
·         The development of potentially dangerous pseudotumors
·         Disruption of DNA
·         Vertigo
·         Anxiety, irritability and depression

When the metal ions become lodged in tissues surrounding the hip joint, inflammation, pain, tissue damage and bone loss can occur, leading to implant failure and the necessity of revision surgery. Stryker issued an Urgent Field Safety Notice to hospitals and physicians in May, 2012. This notice—like the recall notice—stated the risks of the ABG II and Rejuvenate to undergo corrosion, fretting and early implant failure. Many feel the first notice was an attempt to minimize the fear once a recall was issued.

While the ABG II and the Rejuvenate were touted as lasting considerably longer than ceramic and polyethylene implants—even as long as twenty years—many Stryker patients began coming in with such severe problems that revision surgery was necessary after only a few short years. At the time of the recall Stryker stated the failure rate of the ABG II and Rejuvenate as being approximately 12%. It was later discovered that the failure rate may actually be as high as 40% as opposed to the failure rate of a traditional implant of between 4-5%.
The risks of revision surgery—particularly for the Stryker ABG II and Rejuvenate—are higher than the risks of the original surgery and even higher than the risks for other implant revisions. Surgeons dislike performing revision surgery to remove an ABG II or Rejuvenate because of the method of implantation, yet there may be little choice in the matter if a patient begins experiencing symptoms of implant failure or metal toxicity. Part two of this article will more fully detail the surgical procedure for revision of a Stryker ABG II or Rejuvenate hip implant.