Recently, Exactech recalled about 100,000 tibial polyethylene inserts for potential failure and premature wear. The polyethylene inserts were not packaged properly. Instead of a secondary protective mechanism, they were placed in a vacuum bag with little or no oxygen barrier. Exposure to oxygen can cause plastic products to break down prematurely. In some cases, the polyethylene inserts can fail prematurely and cause complications with the implant.
Exactech recalls 100,000 tibial polyethylene inserts
A recall of approximately 100,000 plastic knee and ankle inserts manufactured by Exactech has been issued. These plastic knee and ankle arthroplasty implants contain Polyethylene inserts. The plastics were packaged improperly and allowed oxygen to come in contact with them before they were implanted. This oxidation could lead to premature wear and cause complications with the implants. This could have disastrous results for patients who have undergone knee or ankle replacement surgery.
Patients who have had this type of knee replacement have Exactech Optetrak Recall reported that the product loosened prematurely, causing pain, limited mobility, swelling, and sensitivity. The defective products can also result in an increase in medical costs. The problem can be avoided by monitoring the implant to check for future problems. Patients can also seek revision surgery to replace the defective polyethylene insert or the entire device. However, the company is currently only recalling the polyethylene inserts sold under the Exactech name.
80% of them were improperly packaged in bags
Exactech recently recalled thousands of hip, ankle, and knee replacements due to the defective packaging of their products. Improper packaging can cause plastic implants to break down prematurely, causing severe pain and often the need for revision surgery. This recent recall involves Exactech knee ankle hip replacements, which contain polyethylene plastic inserts. Many of these implants were packaged improperly in vacuum bags. The vacuum bags allowed oxygen to enter the plastic inserts, causing them to degrade prematurely.
The most common reasons for TKR revision are malalignment, instability, and periprosthetic infection. Thankfully, improvements in implant design and manufacturing have significantly reduced the incidence of polyethylene wear. Despite the possibility of tibial insert dislocation, the authors of the study found that the majority of patients who experienced tibial resurfacing experienced a reduction in implant-related revisions.
A defect in the polyethylene liner may lead to premature degradation and fracture. In the worst case scenario, the implanted medical device will fail. Microscopic wear debris released from the defective polyethylene liner may be toxic to body tissue and may enter the joint space. Joint space contains bone, soft tissue, and muscle. Loss of the soft tissues and muscles may lead to joint instability and dislocation. This is why it’s important to monitor polyethylene wear and replacement.
The failure rate of polyethylene inserts in orthopaedic prostheses is largely dependent on the design of the component, which in turn influences the degree of wear. For example, the contact stress in some noncongruent designs exceeded the yield strength of polyethylene. These differences are largely due to subjective failure mode determination. Furthermore, the use of different design and thickness of polyethylene did not allow for direct comparisons.
The oxidation of polyethylene ankle inserts was studied to determine if the material was prone to fatigue. In the present study, polyethylene ankle inserts that were retrieved for loosening or fatigue had oxidation levels above 1.2. This failure rate was higher than those of non-gamma-sterilized polyethylene retrievals. However, the presence of fatigued ankle inserts was not statistically significant.