Why Were the Devices Recalled?
A defective polyethylene liner prompted recalls in both cases. Polyethylene is a common plastic used in joint replacement liners, but issues in Exactech’s design and packaging processes caused the devices to fail.
Exactech Hip Recall
Published as early as March 2020, studies conducted on Exactech’s Connexion GXL Liner, which has been used in three different hip systems, found that the liner exhibited unusual” early excessive polyethylene wear.” The faster rate of wear on Exactech liners causes patients to suffer implant failure during the first five years, which represents a stark deviation from the expected lifespan of modern hip implants.
To help degradation and increase the lifespan of the liner, manufacturers employ a process called “cross-linking”; highly cross-linked polyethylene is shown to be especially resistant to wear. One of the reasons that Exactech’s liner may have shown accelerated wear is because those liners were only “moderately cross-linked.”
Exactech Knee Recall
In its “Urgent Medical Device Correction” letter to healthcare professionals in February 2022, Exactech acknowledged that “most of [their] inserts manufactured since 2004 were packaged in out-of-specification vacuum bags.” These vacuum bags are important because, according to Exactech’s “Design Rationale,” the inserts are placed in vacuum bags to prevent oxidation, or exposure to oxygen. Oxidation resistance is an important safety consideration because the presence of excess oxygen can cause polyethylene to degrade, which can, in turn, cause patients to suffer severe pain, bone loss, and possibly infection.