Stryker Rejuvenate Recall – Is this the Nail in Modular Hip Implant’s Coffin?
For the past few years orthopedic device manufacturers have come under intense scrutiny for selling hip implant devices that fail prematurely. These failures have been due to designing systems that include too many metal parts. It has been determined that when metal touches metal in an implant designed to carry heavy weight and move freely, metal corrodes and erodes, which can release toxic metal into the tissue surrounding the implant, as well as into the bloodstream.
It has also been determined that metal on metal devices fail prematurely when this metal causes tissue death, pseudotumor formation, bone necrosis and device loosening. It is the metal particles circulating in the patient’s system that causes the failure as opposed to the device breaking.
As a result of these failures the FDA has come down pretty hard on the industry, demanding intense post market surveillance of these complications as well as study of the metal poisoning issue.
Two companies have attempted to take advantage of the huge void left in the market, as doctors have stopped implanting metal on metal hips. Wright Medical was first with its modular Pro-Femur hip implant system. The Pro-Femur differs from other hip implants in that the stem and the neck of the device are two separate pieces. These two pieces are inserted into one another and the ball portion of the implant is then placed on the end of the neck. In most devices, the stem and the neck are one piece. There’s only one problem – where the metal stem inserts into the metal neck there is a metal on metal junction. This insertion point is under tremendous stresses once implanted in the patient.
Stryker followed with its Rejuvenate modular system. In order to gain regulatory approval, Stryker claimed its new device was similar to the Pro-Femur. Like the Pro-Femur, the metal Rejuvenate neck inserts into the metal stem.
Since its introduction, the Wright Pro-Femur has been linked to premature fracture of the neck as well as excessive, early failure due to metallosis. Many Wright Pro-Femur lawsuits have been filed.
Now, Stryker’s Rejuvenate has been recalled. It has only been on the market a little over two years. Stryker Rejuvenate lawsuits are sure to follow. One of my client’s doctors told him that he put a hundred of these implants into patients and he fully expects to have to revise every one of them.
Perhaps it’s the end of the road for not only metal on metal bearing surface hips but also these modular systems that depend heavily on metal on a metal interface.
One is really left to wonder what is really wrong with the older, tried and true monoblock hips with non-metal on metal bearing surfaces. They used to last 15 to 20 years. That’s slightly better than two years.