Knee Replacement Lawsuits Overview

Knee Replacements Overview

When knee replacement pain warrants a lawsuit

Knee replacements are used to replace worn-out bones so you can get back to walking, running and dancing without pain. These medical devices have a complicated history that includes lawsuits and recalls. Find out more and see if you should speak with an attorney about a knee replacement lawsuit.

Overview of knee replacement lawsuits

People sue over knee replacements for various legal reasons. The most popular reasons for knee replacement lawsuits are the following:

  • The implant was marketed as safe and effective when the manufacturer knew that it wasn’t
  • The implant’s defects were related to its manufacture, design or marketing
  • The manufacturer knew or should have known about the defects
  • The manufacturer failed to warn consumers about the defects and potential harm

Knee replacement lawsuits generally fall under an area of law referred to as defective products or products liability. (See more about defective products cases.)

Recalls for knee replacement implants

There have been many knee implant devices recalled over the years. Reasons range from device loosening to packaging defects, the latter of which might be a reason you never heard about a specific recall. The recall could have been initiated by the Food & Drug Administration, but it’s far more common that a company recalled its own product for a specific reason.

Enjuris tip: You can search the FDA database of medical device recalls. However, keep in mind that it does not include those knee replacement implants recalled voluntarily by medical device manufacturers.

The following companies have had numerous instances when they needed to claw back a product from public commerce:

  • Biomet: 75 recalls
  • DePuy: 277 recalls
  • Smith & Nephew: 11 recalls
  • Stryker: 118 recalls
  • Wright Medical: 4 recalls
  • Zimmer: 224 recalls

Types of knee replacement lawsuits

Multidistrict litigation for knee replacement patients

Multidistrict litigation (MDL) is a type of federal case that groups together similar cases from all across the country that share similar issues. By putting them together and not duplicating discovery (as in, not having each plaintiff conduct the same interviews when they could be done all at once), the process moves much faster. Medical device lawsuits often take this format, because there are usually a great number of patients who are experiencing complications from the same implant product.

There is currently only one multidistrict litigation for knee implants. This is the Zimmer NexGen Knee MDL (MDL #2272), which has almost 1,800 individual knee replacement lawsuits within it. However, most of those have been dismissed and the overseeing judge has told the remaining parties to negotiate an agreement for the rest.

Class-action knee replacement lawsuits

There are no class actions in regard to knee replacement devices. There are many key differences between an MDL and a class action, though the consensus is that a class action is not a good avenue for medical device lawsuits.

Knee replacement lawsuits by individuals

Individuals can choose to go through state court instead of federal court, unless they have been ordered to join an MDL by the judges in charge of that process.

Your knee replacement lawyer can guide you through the type of lawsuit that makes sense for you.

The following are other companies currently embroiled in knee replacement lawsuits:

  • Arthrex: iBalance Knee (pain and instability)
  • B. Braun (Aesculap Implant Systems): Advanced Surface ceramic coated knees (failure for cement to adhere to bone)
  • DePuy: Attune Knee System (instability and device loosening)
  • Exactech: Optetrack Knee (wear and tear leading to device failure)
  • Zimmer: NexGen (premature device loosening) and Persona Knee (defective screws, device loosening)

What to do if you think you may have a knee replacement lawsuit

First, talk with your surgeon to see what must be done if you are experiencing pain in one or both of your knees. You might be able to fix the issue without surgical intervention. The most important thing is to get you out of pain and make sure your implant is not failing.

If you’ve already explored pain from your knee replacement implant with your doctor, talk to an attorney.

Each state has a statute of limitations, which is the time available to file your knee replacement lawsuit. Once you are past that time frame, you lose the ability to file. Some states only offer one year for cases, so get this done. A lawyer will be able to preserve your claim.

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Keep in mind, however, that defective products cases take a long, long time to finish. It might be a decade before you see any money, if at all. Make sure not to get your hopes too high, too soon.

Products liability law (AKA defective products law) is unique. You’ll want to look for a products liability/defective products lawyer who has many years of experience, preferably also with knee replacement lawsuits.

If you have not met with a lawyer yet, consider looking through the Enjuris lawyer directory for someone in your state who can help.

Background on knee replacement surgeries

Who needs a knee replacement?

The likelihood of needing a knee replacement surgery is trending upward as national life expectancy increases. When medications, physical therapy or lifestyle changes fail, doctors will recommend this intervention.

By 2030, the number of knee replacements completed per year is expected to increase by 673%. No, that is not a typo. That’s 3.5 million of these procedures per year. One in two Americans will experience osteoarthritis, the most common form of arthritis, which is caused by the degeneration of cartilage between bones. That, along with obesity numbers rising (which only puts stress on knees holding up extra weight), is only serving to make knee replacements more prevalent and popular.

More than 90% of patients who have a total knee replacement find their pain is reduced. Tweet this

A knee might also need to be replaced because of environmental or hereditary conditions. These procedures (a total knee replacement or a partial knee replacement) are generally recommended by health professionals when patients cannot live without pain or function in their daily lives.

These are, by and large, successful surgeries; according to the American Academy of Orthopaedic Surgeons, more than 90% of patients who receive a total knee replacement feel a reduction in pain. The device itself can last for more than 20 years.

What is the difference between a total and partial knee replacement?

A total knee replacement is when surgeons resurface bones in all parts of the knee joint. The end of the femur, the patella and the top of the tibia will be resurfaced, and ligaments supporting the knee might be left in place or removed depending on their condition. Existing cartilage is normally replaced with a plastic cushion.

A partial knee replacement resurfaces one or two sides of the knee, called either a unicompartmental or bicompartmental procedure. These procedures can range from replacing the end of the thigh bone with metal and resurfacing the back of the patella to removing bone from the tibia to take weight off the damaged part of the knee.

Hereditary conditions that can make knee replacements necessary

A hereditary condition is something that develops because of genetics. This can include genetic diseases caused by an abnormality or some kind of mutation. Basically, it’s your parents’ fault, so feel free to blame them.

Some genetic conditions that could cause knee pain include the following:

  • Developmental abnormalities
  • Rheumatoid arthritis
  • Juvenile arthritis
  • Osteoarthritis

Acute and environmental conditions that can lead to knee replacements

On the other side of the spectrum, knee replacements can be necessitated by acute or environmental conditions; patients who bang up their knees simply in pursuit of fun, outdoorsy activities. Maybe they were playing sports, or maybe they were ballerinas with poor form. Maybe they were ultramarathon runners. Whatever the reason, those bones must be removed because the cartilage has worn away, leaving the bones to rub against each other.

Some acute conditions causing knee pain include:

  • Emergency trauma
  • Sports injuries
  • Repeated falls
  • Obesity
  • Avascular necrosis (bone death)

A brief history of knee replacement implants

The total knee replacement (TKR) is one of the most important surgical advances of the 20th century. Knee replacements, believe it or not, date back to the late 1800s.

In 1890, German surgeon Themistocles Gluck was the first to surgically implant joint hinges made of ivory.

The first hinges for knee replacement were created in 1860 and made of ivory! Tweet this

The Walldius hinge joint was created in 1951, originally manufactured in acrylic before changing to cobalt and chrome in 1958.

This hinge joint suffered from early failure, so surgeons and developers kept trying. This led John Charnley to create the cemented metal-on-polyethylene total hip arthroplasty in the early 1960s. Improvements kept being made in the schematics of the device, where they were placed and what materials were used, which brings us to the modern-day knee replacement implants.

How does an artificial knee replacement work?

The knee joint is formed where the femur (AKA the thigh bone) meets the tibia (shinbone) and fibula (the bone next to the tibia). The patella, or kneecap, moves against the femur and rests atop the knee. Ligaments, muscles and cartilage bridge these bones and form a hinge, which creates flexibility and allows for movement.

When it comes to knee implants, only the tibia, patella and femur are affected, whether by resurfacing or replacing. Knee replacements are made in a variety of plastics, ceramics and metals:

Tibial component: This part is attached to the tibia with a stem inserted into the bone for stability. These pieces are generally in two parts and consist of a mix of plastic and metal.

Femoral component: This attaches to the end of the femur, allowing the patellar component to slide up and down when the knee bends.

Patellar component: This piece is intended to match the resurfaced patella and must properly align with the femoral component in order to work correctly. Tendons hold this piece in place.

Enjuris tip: Experiencing pain after a knee replacement? Speak with your surgeon first and eliminate all other possibilities before pursuing a knee replacement lawsuit.

The knee replacement components will be inserted into place and sometimes cemented for additional stability. If the patient is younger, the doctor will likely opt out of using cement because the patient’s bone structure is strong enough without it.

Knee replacement manufacturers and implants


Four knee replacement medical device companies currently dominate the market, which has proven to be especially lucrative. The following is a list of the most popular producers and implants, though it is by no means a comprehensive list of devices or companies that exist.


DePuy Synthes

DePuy Synthes is a Johnson & Johnson subsidiary, the second-largest hip and knee implant manufacturer in the world. In 2016, the company had an estimated $1.5 billion in sales of knee implant devices. Its knee replacement implants include:

  • Attune
  • LCS Complete
  • Sigma
  • S-ROM Noiles

Stryker Corporation

Stryker Corporation also reported nearly $1.5 billion in sales in 2016 for its knee implant devices:

  • Avon Patello-Femoral
  • Duracon TS
  • Scorpio
  • Triathlon
  • Triathlon Tritanium

Smith & Nephew

Smith & Nephew, a U.K.-based company, reported revenue of approximately $932 million in 2016 for its knee replacement devices. Its claim to fame is a proprietary zirconium blend that is supposed to have less wear than plastic versions. Smith & Nephew knee replacement implants include:

  • Genesis II
  • Journey II
  • Legion


Zimmer and Biomet merged in 2014 and together hold approximately 35% market share of the global hip and knee replacement market. They produce about 25% of knee replacement implants worldwide. Some of their most prevalent knee replacement implant products include:

  • Gender Solutions
  • NexGen
  • Oxford
  • Persona
  • Vanguard Individualized Design

Complications related to pain after knee replacement surgery

Most patients who receive a total or partial knee replacement end up re-joining life at a better pace, as they’re able to move without pain and walk more normally. However, that is not to say that complications and pain after knee replacement surgery don’t occur. We all know that even the most routine medical procedures can cause problems.

Here are the most common issues that patients report. These may lead to pain after knee replacement surgery or other symptoms:

  • Device loosening
  • Metallosis (AKA metal poisoning – read about metallosis in relation to hip replacements, as the principle is the same): the metal implant pieces rub together, releasing particles into the bloodstream and joint
  • Joint infection (less than 2% of patients)
  • Blood clots (1.2% of patients with a total knee replacement): Men over 70 years old are at the highest risk of this development
  • Stiffness
  • Swelling
  • Pain and soreness
  • Nerve and tissue damage
Knee replacement implants are intended to last 15 years. Did yours? Tweet this

Knee implants are intended to last at least 15 years, though many extend beyond 20 years. Other times, patients are required to undergo revision surgeries because of knee replacement pain and other difficulties. If the implant wears out, for instance, correction will be necessary. More surgeries can cause more complications.

Ready to inquire about a knee replacement lawsuit?

If you feel your complications and pain after knee replacement may warrant a lawsuit, these resources will be helpful:

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