Unacceptable Cobalt and Chromium Levels in the Stryker Rejuvenate Hip Implant Patient

Chromium and cobalt toxicity and poisoning are very serious health issues, and those who have an all-metal or partial metal implant should have regular blood tests performed in order to carefully monitor those levels. While those with an all-metal hip implant (such as the Pinnacle or ASR) would likely have much higher levels of cobalt and chromium than those with a Stryker Rejuvenate hip implant, the Rejuvenate revision surgery is much more difficult and risky to the patient. The Rejuvenate is constructed using a ceramic ball, meaning there are not the large metal surfaces of the ball and cup to rub against one another, causing corrosion and metal ions to shear away into the body.

However, when the recall for the Rejuvenate was issued, Stryker stated the risk of fretting and corrosion at the neck juncture and since that time it has been noted that the metal trundles located on either end of the neck piece of the implant can trap body fluids and corrode in the same way. When the Rejuvenate patient experiences corrosion, metal ion release and subsequent pain and health issues, many times there is no option other than for the patient to undergo revision surgery. Unlike the ASR or the Pinnacle in which the acetabular cup or the liner may be replaced during revision, should the Rejuvenate patient require revision surgery the entire implant must be removed. Because the stem of the Rejuvenate is implanted deeply into the femur during the original surgery, revision surgery requires the stem to be dug away from the femoral bone-a potentially dangerous surgical procedure. 

Once blood tests show increases in cobalt and chromium in the body, Rejuvenate recipients may wonder what levels of these metals are considered dangerous. The normal, healthy person has approximately 0.5 parts per billion of cobalt and chromium in their body which occurs naturally. Many doctors believe that anything over two parts per billion of cobalt and chromium in the body brings health risks to the implant recipient. Others believe that anything up to five parts per billion is relatively safe and others put that number at seven parts per billion. Once corrosion occurs in the body and metal ions are released, it is impossible to determine how the individual person will react to those toxic metals.

Some people whose blood tests show extremely high levels of cobalt and chromium have relatively few symptoms, while others with levels of cobalt and chromium considered “acceptable” can be very ill. The effects of metals in the body and tissue damage and death from those tiny metal shards are largely issues with no clear medical resolution. Because of the large surface areas of the ASR and Pinnacle, cobalt and chromium numbers as high as in the twenties or even higher may be acceptable however with the Rejuvenate even a 2 or 3 can be a major concern because it is coming from a joint which is not supposed to wear at all. Therefore a number such as 3 can be indicative serious wear; while numbers between 7-10 in another implant may not prompt removal, numbers as high as 3 could prompt removal in a Rejuvenate.

It’s important for the Stryker Rejuvenate hip implant recipient to have regular blood work done as well as other tests recommended by their physician. These tests may include x-rays, an MRI and a bone scan. Should the levels of cobalt and chromiumin the blood increase or should the patient have any unusual or worsening pain in the hip or groin area, it could be necessary to undergo revision surgery.