The Stryker Corp. manufactures thousands of medical devices, including hip and knee implants. But, the company recalled two of its hip implants, the Rejuvenate and ABG II Modular-Neck Hip Stem, in 2012. Its TMZF femoral stems and LFIT (Anatomic) cobalt-chromium femoral head also face scrutiny and lawsuits.
Michigan-based Stryker Corp. began as the Orthopedic Frame Company in the 1940s. Over the years the company expanded and now markets 57,000 products worldwide. Its net sales reached $9.9 billion in 2015, Becker’s Spine Review Reported.
A large portion of its profits — $4.2 billion in 2015 — comes from its orthopaedics division. This includes its hip and knee implants. The company manufactures many of the implants with its proprietary titanium TMZF alloy and interchangeable components which the company says allows surgeons more choices to better fit patients. The stems have a PureFix HA coating, designed to help bone grow around the implant for a better fit.
Unlike typical hip implant systems, which include a one-piece neck and stem called a monoblock design, Stryker’s Rejuvenate, ABG II and other TMZF systems include several neck and stem components. Stryker designed these modular, interchangeable systems to give surgeons greater flexibility by offering them more anatomically correct implant components that could be custom-fitted to patients.
The ABG II system has eight right stems, eight left stems and 10 modular necks, which are supposed to offer greater stability and minimal bone stress. Stryker marketed the Rejuvenate hip, with six stems and 16 necks, to younger patients. These devices were supposed to be longer lasting and have a better range of motion.
Stryker’s proprietary titanium alloy blend mixes titanium, molybdenum, zirconium and iron. The company claimed that its patented blend resisted the effects of corrosion and fretting — small particles of metal flaking off the implant. Stryker says this alloy “more closely resembles that of bone,” and it is 20 percent stronger than other titanium alloys.
Unfortunately, post-market data revealed evidence of corrosion and fretting and Stryker recalled the Rejuvenate and ABG II systems. The recall came too late for some patients. Patients claim the devices caused serious side effects, including loosening of the implant and the release of toxic metals into patients — complications that are leading to a number of lawsuits against Stryker.
Now, Stryker’s other TMZF hip components — Accolade, Citation and Meridian — may also cause issues. These titanium alloy implants combined with other metal implants may cause problems similar to those caused by the ABG II and Rejuvenate.
Stryker Hip Stem Complications
Recent recalls of hip implants focused on the metal-on-metal ball-and-socket components, which can release metallic debris into the body during normal wear and tear. Stryker’s two modular-neck hip stem systems are not like other metal-on-metal devices, since they do not involve a metal ball rubbing against a metal socket. However, because the Stryker necks are made of chromium and cobalt, and the stems have a titanium coating, they do have a metal-on-metal junction. And they can cause the same complications as other defective hip implants.
In April 2012, Stryker issued an “Urgent Safety Alert” to surgeons and hospital risk managers for the two hip replacement systems. The alert listed the potential hazards in these devices, including: “Excessive metal debris and/or ion generation,” caused by “fretting and/or corrosion at or about the modular neck junction,” which “may lead to increased metal ion generation in the surrounding joint space.”
For years, medical researchers questioned the safety of metal-on-metal hip devices because of the tendency for metal components to rub against one another, depositing minute shards of metal into a patient’s tissues, bones or bloodstream. These particles cause inflammation or death of surrounding tissues called adverse local tissue reaction (ALTR).
|Contact between metal ions and surrounding cells can result in ALTR, which can include:|
|Metallosis (metal toxicity from grinding metal components)|
|Necrosis (premature tissue death)|
|Osteolysis (bone dissolution)|
|Pain requiring revision surgery|
Stryker Hip Stem Recall
On July 6, 2012, the FDA received more than 60 adverse event reports of metal toxicity requiring revision surgery. Stryker recalled its Rejuvenate and ABG II hip components in the United States and stopped all global production and sale of the devices.
The company advised patients fitted with modular-neck hip implant systems who experience persistent pain to undergo medical evaluations — including X-rays, MRIs and blood tests — to check for dangerously high metal ion levels. Medical professionals suggest that ALTR will generally require operative intervention and likely revision surgery with ceramic-on-metal modular junction replacement.
Since the stem components of a hip implant connect deep into the patient’s femur, this type of revision surgery is considered particularly difficult for the physician and traumatic for the patient. In fact, there is a risk that the femur will fracture during revision surgery.
One patient, Dianne Pingel, had to have her femur reconstructed after multiple fractures developed in the thighbone during revision surgery. Her surgeon told her that the metal ions from her hip implant caused the tissue and bone to die, weakening the bone and making it susceptible to constant dislocation and fracture.
Some patients undergo multiple revision surgeries to correct problems such as fractures, dislocations and infections. Since the price of one hip replacement surgery can be as high as $223,000 depending on the hospital and doctor, the cost of multiple surgeries can climb quickly.
While not recalled in the U.S., Stryker’s line of TMZF components may also cause these same complications. These components include:
- Accolade TMZF femoral stem
- Citation TMZF femoral stem
- Meridian TMZF femoral stem
- LFIT (Anatomic) cobalt-chromium femoral head (V40 taper)
In September 2015 and August 2016, Health Canada issued a recall for the LFIT Cobalt-chromium v40 Femoral Head. According to the first notice, customers complained the LFIT V40 heads manufactured from July 7, 2014 to August 15, 2014 could not be assembled with the V40 stem. Health Canada issued the second recall because “Stryker has received higher than expected complaints of taper lock failure for specific lots of certain sizes of LFIT Anatomic COCR V40TM Femoral Heads manufactured prior to 2011.”
Stryker Hip Lawsuits
Medical manufacturers are ethically and legally responsible for designing safe products. They are also obligated to warn consumers about products that are unsafe in sufficient time to prevent harm and/or device failure. When manufacturers neglect these responsibilities, victims can sue for compensation. Amounts received can cover the costs of past and future medical treatments, additional surgeries, and loss of wages or livelihood.
Lawsuits filed against Stryker accuse the company of negligence because it did not adequately test the Rejuvenate and ABG II before releasing them. They also claim the company failed to warn patients and doctors about the risk of side effects such as excessive ions in the blood and tissues surrounding the implant. The first four Stryker lawsuits were settled in December 2013 for an undisclosed amount.
In 2014, the company agreed to pay $1.43 billion to settle several thousand claims.