In August 2016 Stryker Corporation voluntarily recalled certain lots of its LFIT™ Anatomic CoCr V40 Femoral Head, a component of artificial hips. According to Stryker, the company has received higher than expected complaints of taper lock failure with components made prior to 2011.
The U.S. Food and Drug Administration (FDA) posted a notice of the recall to their website on November 9, 2016. The announcement comes on the heels of regulatory action in Canada, the United Kingdom, and Australia. The LFIT™ Anatomic CoCr V40 Femoral Head is the third artificial hip product that the company has had to recall in 5 years.
For patients with an affected implant, the Stryker recall is disturbing. There are a number of potential complications associated with the device, which may cause severe pain, inflammation, loss of mobility, and metallosis, among other problems.
Component Failure and Side Effects
To understand what’s wrong with the component, it’s important to know how the whole implant is supposed to work.
The “ball and socket” connection, which joins the femur (thigh bone) to the hip, allows humans a healthy balance of movement and stability. The rounded head of the femur, the “ball,” moves inside the hip’s “socket,” known as the acetabulum.
The LFIT™ Anatomic CoCr V40 Femoral Head acts like the ball inside the socket. The head fits inside a cup that is attached to the hip. The head is also connected to the femoral stem, another component, which is inserted into the femur. The taper lock is what connects the femoral head to the femoral stem. In this way, the joint between hip and femur is replaced by the implant.
Taper lock failure may jeopardize the connection between the femoral head and femoral stem. Potential hazards associated with this issue may include:
- Disassociation of femoral head from hip stem
- Fractured hip stem trunnion
- Excessive metallic debris
- Insufficient range of motion
- Insufficient soft tissue tension
- Loss of implant: bone fixation strength
- Excessive wear debris
- Implant construct with a shortened neck length
When the taper lock fails, the LFIT™ Anatomic CoCr V40 does not work like it is supposed to, leading to serious and unnecessary side effects. According to the Australia’s Therapeutic Goods Association (TGA), people with defective LFIT™ Anatomic CoCr V40 Femoral Heads may suffer from:
- Loss of mobility
- Adverse local tissue reaction
- Joint instability
- Broken bones around the components
- Leg length discrepancy
- Need for revision surgery
The pain can come gradually along with a decrease in range of motion. But device failures can happen suddenly, resulting in broken bones or the immediate need for revision surgery. In the last 5 years, there have been over 100 adverse events reported to the FDA associated with the LFIT™ Anatomic CoCr V40.
In addition to these potentially life-altering injuries, a defective taper lock may result in the release of toxic metals into the body – leading to metal poisoning known as metallosis. Unwanted metal debris may also cause inflammation, which can lead to fluid buildup known as a pseudotumor around the implant. All of this from a product that is supposed to improve patient quality of life.
The Future Needs a Healthier Balance
According to Stryker, hip replacements represent a $5.8 Billion market, of which Stryker’s share is about 22 percent. Like many successful medical technology companies, Stryker prides itself on growth and innovation. But three major recalls in 5 years have many people questioning Stryker’s balance between innovative products and patient safety. How many recalls will it take before Stryker prioritizes safety first?
It must not be overlooked that medical device recalls are the result of real people getting injured by products that are supposed to help them. Recalls are, by definition, too late to protect some of the people affected by the product. And, when it comes to artificial hips, revision surgeries should not become the norm.
Hopefully, this recall will make it easier for patients with the defective implant to get the help and support they deserve.