The Attune Artificial Knee

The DePuy Synthes Attune artificial knee is marketed as an “innovative, comprehensive, integrated knee system” that provides stability, strength, and a greater range of motion post-surgery. This novel design was created to be a better approach to traditional knee replacements. But many people have experienced complete failure of their Attune knees shockingly soon after surgery.

To understand what goes wrong, let’s first consider how an artificial knee is supposed to work. The replacement joint has to sit right where the knee originally was, connecting the femur, or thigh bone, with the tibia, or shin bone. The new knee must be firmly attached to both bones or it won’t work. Imagine a single hinge holding a door onto a wall and allowing it to swing. If the hinge comes detached from either the wall or the door, the door will pull away from the wall and fall down as it swings.

Last year, a group of orthopedic surgeons reported in The Journal of Knee Surgery that this is exactly what happens with a disconcertingly large proportion of Attune artificial knees. While the replacement joint remains solidly cemented to the femur, the lower bond to the shin has a tendency to fail. The cement that should hold the knee to the tibia binds to the bone but not to the Attune device itself. Therefore, the detached joint floats, and just like the failed hinge that allows the door to fall, the replacement knee can’t hold any weight.

People with defective Attune knees experience significant knee pain, especially when they try to bear weight on the knee when standing or walking, as well as a restricted range of motion. The study revealed that these problems sometimes occurred within just a few months of the original knee replacement.

The only way to correct a failed Attune knee is to undergo a second or “revision” surgery. That second surgery—where the useless cement must be removed from the tibia and the solid femur connection must be broken—is more involved and more painful than the initial knee replacement procedure. To make matters worse, the surgeons’ report indicated that the separated knee generally doesn’t show up on X-rays; it can only be detected during the revision surgery. In other words, a doctor may not realize that the replaced knee has failed.

The Attune knee’s defects are further evident in the U.S. Food and Drug Administration’s Medical Device Adverse Events (MAUDE) database. Even though MAUDE is a self-reporting system, such that only the manufacturer, DePuy Synthes, can report its knees’ failures, there are dozens of recent reports. The Attune knee has been redesigned and may now be less prone to separation from the shin bone, but the original design has not been recalled, and the recipients of that faulty device have been left to fend for themselves.

Fortunately, DePuy Synthes is now being forced to answer for these defects in court.

The Attune Lawsuit(s)

Last September, a law firm filed the first lawsuit involving a defective Attune knee in Tuscaloosa County, Alabama. The case alleges that its client’s artificial knee failed prematurely, resulting in substantial pain, delayed recovery, and significant medical expenses. Expect to see more lawsuits in the future involving Attune knees. These cases are likely to involve not only damages for pain and suffering but also for the costs of the second replacement knee surgery and the accompanying physical therapy.

Have you had a knee replacement that ultimately failed or that caused more problems than it solved? We can advise you whether you may have a case against the manufacturer or another involved party. Please contact us to talk with a lawyer about your situation.

October 2016 was set to be an important month for thousands of people injured by the Zimmer NexGen artificial knee. The second “bellwether” trial was scheduled. Bellwether trials involve representative cases that are used to educate the defendants and the plaintiffs on what certain juries thinks may be proper results for these kinds of cases. After several bellwether trials, both sides often come together and work out a global settlement based in large part on results from these bellwether trials.

Unfortunately for the plaintiffs in the Zimmer NexGen MDL, the latest bellwether case never reached the jury. On October 21, 2016, Judge Rebecca Pallmeyer, the federal judge overseeing the Zimmer NexGen MDL, granted summary judgment for Zimmer and the other defendants. Which means the case is over.

Summary Judgment

Summary judgment is a final judgment entered by the judge prior to trial. Essentially, the judge determines that no material factual issues remain in dispute and that one side is entitled to judgment “as a matter of law.” For the most part, summary judgment is a defensive tool, and defense lawyers will file a motion for summary judgment and will argue to the court that even taking the facts in a light most favorable to the plaintiff, the defendant is still entitled to judgment without the need for a jury trial.

This is exactly what happened last week on the eve of the second bellwether trial in the Zimmer NexGen MDL. In a 43-page Order, Judge Pallmeyer held that the plaintiffs failed to present adequate evidence that the design of the Zimmer NexGen knee caused the plaintiff’s alleged injury, and that the plaintiffs failed to show that the warnings accompanying the medical device were inadequate.

more Judge Rejects Plaintiffs’ Expert Witness

The plaintiff, Theodore Joas, was implanted with the Zimmer NexGen “Flex” knee. He had to undergo revision surgery in 2014 because the NexGen tibial component became loose and caused pain and complications. Mr. Joas and his wife sued Zimmer for several causes of action, but the key claims appear to have been (1) design defect, (2) failure to warn, (3) negligence and (4) punitive damages.

The key decision in the summary judgment order was the judge’s rejection of the plaintiffs’ expert witness. Once the expert witness was excluded as unreliable, the case collapsed.

The plaintiffs offered the testimony of Dr. Joseph Fetto. He testified that the Zimmer NexGen flex knee “puts excessive stress” on the cement and component “and can lead to early failure.” (Order, p. 12)

Judge Pallmeyer rejected Dr. Fetto’s expert opinion as not valid. She wrote in her order that Dr. Fetto failed to refer to scientific literature or to “give any explanation for why the implant design, and asymmetric loading generally, causes . . . loosening.” (Order, p. 12) The judge wrote at length about the reasons why Dr. Fetto’s testimony is unreliable, ultimately concluding that Dr. Fetto has not “given the court sufficient basis to conclude that his opinion is reliable.” (Order, p. 17)

Excluding an expert means the expert cannot testify at trial, that his expert opinions are not sufficiently grounded in science to permit him to present an opinion to a jury. In a product liability case, it is essentially a death sentence for a plaintiff’s case. And it turned out to be for the plaintiff in this case, Mr. Joas.

Judge Pallmeyer first granted summary judgment as to all claims the plaintiffs did not defend at the summary judgment hearing. That was the easy part, and plaintiffs would have seen that coming. Then the judge awarded summary judgment as to the design defect, failure to warn, negligent design, and punitive damages claims. She pointed out that because plantiffs designated only Dr. Fetto as an expert witness, and because his testimony was (now) excluded, the plaintiffs were left with no expert to testify that a defect in Mr. Joas’s Zimmer NexGen knee was the cause of his injuries.

Judge Pallmeyer granted summary judgment as to plaintiffs’ failure to warn claim based on the defense of the learned intermediary doctrine, which I write about here. In Mr. Joas’ case, the implant surgeon admitted he did not read the package insert for the Zimmer NexGen flex knee components. Because of the surgeon’s confession that he did not read the product warnings, plaintiffs cannot prove “that an improved warning would have led to a different outcome for Joas’s knee.” (Order, p. 41) Sadly, this makes sense.

“The Trial Date is Stricken”

Like a slamming door, the last sentence of Judge Pallmeyer’s Order must have been startling to the plaintiffs: “The trial date is stricken.” This of course means that, “in light of what I just wrote, this case does not deserve a jury trial. Case closed.”

So far, the judge in the Zimmer NexGen MDL has not been impressed with the plaintiffs’ arguments. Judge Pallmeyer issued a Lone Pine Order in June, 2016, which you can read about here, and which sets out heightened requirements for the plaintiffs in order to reach a trial by jury. The latest summary judgment order, coming as it does in the second bellwether case, is a major setback for the remaining plaintiffs in the NexGen litigation. Still, with almost 6,000 plaintiffs remaining in the MDL, there is reason to believe this product was defectively or negligently designed.

Do You Qualify for the Zimmer NexGen MDL?

The threshold requirements to participate in the MDL are (1) to show implantation of the relevant Zimmer NexGen knee components, and (2) to show through the medical records clear evidence of loosening. Loosening is when the artificial knee components begin to move in the patient’s leg and separate from the bone. A loose artificial knee can cause major complications and eventually require replacement and revision surgery. When a patient complains to a doctor about knee pain after a total knee arthroplasty, the doctor will order an X-ray and look for radiolucent lines, which are spaces between the artificial knee component and the patient’s bone. These spaces can cause serious problems for a patient with an artificial knee, and can be the first signs of an artificial knee failure.

If you have a Zimmer NexGen knee implanted, and it failed, and the failure led to revision surgery, you should find a good product liability attorney to review your case thoroughly and see if it qualifies under the latest guidelines. But as Mr. Joas will tell you: you’ll need a strong expert on causation to overcome Judge Pallmeyer’s critical eye.

Second Bellwether Case Caption: Joas, et al. v. Zimmer Inc., No. 13-9216 (N.D. Illinois)

Note: Photos for illustration only.