According to the most recent Zimmer Biomet annual report, knee replacement devices make up the largest portion of the company’s income, accounting for $2.3 billion in sales in 2015 – nearly 40% of the company’s $6 billion in annual revenue. Most of those sales take place in the Americas, though the company also sells products in Europe and Asia as well. Zimmer Biomet sells more knee replacement devices than any other company in the world.
Brand names under which Zimmer markets its knee devices include Persona, NexGen, Oxford, and Vanguard. Over the years, Zimmer has experienced a number of problems due to the design of its knee replacement devices, which has caused complications for patients and led to voluntary recalls, regulatory actions, and lawsuits.
Purpose of Zimmer Knee Devices
Knee replacement (arthroplasty) is most commonly used to repair damage to the knee and to reduce or eliminate pain due to joint wear and tear. Damage and joint pain can come about as a result of injury, inflammatory conditions such as arthritis, or simply due to aging. Although most people who undergo a knee replacement surgery are older than 50, there is no specific age at which knee surgery is generally administered. The American Academy of Orthopedic Surgeons estimates that 600,000 knee replacements are performed in the U.S. each year.
Zimmer is one of several medical device companies that makes knee replacement systems. These systems can be used to replace the entire knee joint, a part of the joint, or who need knee joint revision. Which devices are used depends on the needs of the patient and the purpose of the arthroplasty surgery.
Zimmer Knee Replacement Systems
|Total Knee Systems||Partial Knee Systems||Knee Revision Systems|
|Used to replace the entire knee joint with components attached to the fibula and tibia, as well as in place of the cartilage around the knee.||In some cases, only a portion of the knee is damaged and needs replacement. Partial knee systems provide a way to repair knees in such cases. This is sometimes called unicompartmental knee replacement.||Over time, a knee replacement device may wear down, requiring revision surgery to repair the knee replacement.|
In addition, Zimmer sells knee replacement components, instruments, and cartilage repair products.
Knee Replacement Safety Concerns
As the most common type of joint replacement surgery, knee replacements are generally considered safe. More than 90 percent of people who undergo knee surgery experience a reduction in knee pain, and their activities and capabilities often return to at or near pre-pain levels.
That said, there are still a number of safety concerns and problems that can occur when undergoing a knee replacement surgery. These include:
Surgical Complications: Every surgery comes with some risk of complications, such as infection, heart attack, or stroke due to trauma caused by the surgery itself. Small infections are typically treated with antibiotic medications.
Blood Clots: One of the biggest post-surgical risks of knee replacement is blood clots, which can become life threatening if they come loose and travel to the lungs. Preventing blood clots usually involves performing leg exercises and taking blood thinner medications.
Nerve Damage: In very rare cases, nerve damage can occur to the knee and nearby areas of the leg.
In addition to these common safety concerns, in some cases the knee replacement devices themselves may be defective. Medical device companies are required by law to perform clinical trials, follow published regulations, and receive approval from the FDA. Nonetheless, when developing medical devices, design and manufacturing mistakes can occur, causing pain, instability, and other problems down the road for patients who have undergone arthroplasty.
Zimmer Knee Replacement Recalls
Zimmer and its predecessor companies (such as Biomet) have historically had a number of problems with their knee replacement devices. Some of these have affected large numbers of patients, leading to recalls and additional surgeries required to repair or replace the malfunctioning parts.
Persona Trabecular Metal Tibial Plate Recall
On January 28, 2015, Zimmer initiated a voluntary recall of its Persona Trabecular Metal Tibial Plate, a component of the company’s Persona-branded knee replacement devices. According to the recall notice, Zimmer had received an increase in complaints that the tibial plates were coming loose and forming “radiolucent lines” – that is, linear spaces between the device and the joint cement holding it in place.
More than 11,600 knee replacement devices were affected by this recall. Zimmer instructed hospitals, orthopedic surgeons, and distributors to return the defective devices. It is unclear from the recall notice how many people may have already had the malfunctioning devices surgically implanted.
Other Zimmer Knee Device Recalls
Zimmer has issued a number of other recalls on parts related to its knee replacement devices. Many of these recalls were instituted before any of the knee replacement components could be surgically implanted into patients. However, there is still the risk that some of the components were not returned by the distributors, hospitals, or doctors to whom they were sent, and it is possible some of them may have been used in arthroplasty operations.
In 2010, Zimmer recalled the MIS Tibial Component after the company received reports about improperly locking screws and stems on the device. Over 100 people filed complaints to the FDA that the device was coming loose, which led to the need for knee revision surgery.
Sulzer Medica, a company acquired by Zimmer in 2003, paid $1 billion in 2002 to settle thousands of legal actions filed by customers who received joint implants in their knees and hips. As it turned out, the manufacturing process for the company’s Natural Knee II Tibial Baseplate implant had left an oily substance on the device, which caused problems for patients up to a year later.
The table below provides a summary of other recalls that Zimmer has conducted over the last several years.
|Date||Product/Component Recalled||# Recalled|
|January 11, 2016||NexGen Knee system components||88,389|
|March 17, 2016||Persona The Personalized Knee System Articular Surface Posterior Stabilized (PS) Left||Unknown|
|December 3, 2015||NexGEN System REF 5980-37-01 Tibial Component Size Stemmed 3 Precoat||384|
|October 2, 2015||Natural Knee II Revision Femoral Stem||352|
|April 30, 2015||PRI Femoral Impactor Block||1,689|
|March 10, 2015||Persona Anterior Referencing Sizer with Locking Boom||688|
|January 28, 2015||Persona Trabecular Metal Tibial Plate||11,658|
|November 24, 2014||Zimmer PERSONA Tibial Articular Surface Inserter||1,091|
|October 9, 2014||Persona Stemmed 5 Degree Cemented Tibia||138|
|October 7, 2014||Persona Tibial Articular Surface Inserter||618|
|August 7, 2014||Persona The Personalized Knee System – Constrained Tibial Articular Surface||77,737|
|July 30, 2014||Zimmer PERSONA Distal Valgus Alignment Guide||2,248|
|July 22, 2014||Knee Instrument Fixation Screws, Knee Stem Extensions & Impactor Sleeve||972,125|
|July 10, 2014||Natural-Knee System Patella Bushings||8,638|
|July 1, 2014||Persona The Personalized Knee System – Tibial General Instrument Tray||190|
|May 19, 2014||NexGen Complete Knee Solution||41,180|
|February 25, 2014||Gender Solutions Natural-Knee – Flex System||3,638|
|November 19, 2013||NexGen Complete Knee Solution – Patella Drill Guide, Articular Surface Provisional||3,027|
|October 31, 2013||NexGen Complete Knee Solutions Stemmed Tibial Component Precoat||128|
|August 30, 2013||Natural-Knee Flex – Femoral Component, Natural Knee II – Femoral Component, Zimmer Unicompartmental Knee – Femoral Component||80,007|
|June 10, 2013||Persona The Personalized Knee System – Tibial Articular Surface||70,986|
|June 7, 2013||NexGen Cruciate Retaining Complete Knee System – Micro Femurs, Articular Surface, Patellae||192,355|
|November 14, 2012||Persona Knee System – Natural Tibia, Tibial Sizing Plate, Tibial Drill, Tibial Drill Guide, and Tibial Broach||2,482|
|September 21, 2012||NexGen CompleteKnee Solution – Stemmed Nonaugmentable Tibial component||123|
Zimmer Knee Replacement Lawsuits
Due to various problems related to its NexGen Knee Replacement Systems, including issues that have led to recalls of various components, Zimmer has faced a number of lawsuits from patients around the United States. Most of these knee replacement lawsuits are pending in a federal multidistrict litigation (MDL) system in the Northern District of Illinois.
MDL lawsuits allow similar cases to be handled by the same judge and court, helping the cases go through the process faster and more efficiently, while allowing individual plaintiffs to keep their cases separate from others (unlike a class action lawsuit). The MDL case for Zimmer knee devices is MDL 2272, MDL In Re: Zimmer Nexgen Knee Implant Products Liability Litigation. The MDL was created in 2011, and the first cases took place in October 2015. As of October 2016, there were more than 1,700 lawsuits that had been transferred to MDL 2272.