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Section h3, h6: the associated devices were returned and evaluated.The visual inspection revealed coating worn completely off in some places, and the insert appears to have suffered wear and damage.A lab analysis performed on the device revealed that based on the observation of the retrieved parts, the poly insert was floating on the anterior aspects of the knee joint.The inferior-posterior surface of the insert was plastically deformed while the inferior-anterior surface was reasonably untouched indicating the insert was disassociated anteriorly.This condition allowed the knee femoral component to articulate directly on the tibial tray.Knowing the bulk hardness of zirconium ally is nearly 50% lower than that of the titanium alloy could result the notable femoral knee condyle.The disassociation of the insert from the tibial tray is possible when a wrong size combination is used in this case.The clinical/medical investigation concluded that, based on the provided chartstik photo and review of the lgn cr & ps fem/isrt interchangeability chart, a sizing discrepancy within the primary total knee construct was noted and would be related to user selection of components.The wear on the femoral component appears to be from direct femoral articulation onto the tibial baseplate.No contributing clinical factors can be definitively concluded based on the limited information provided.The patient impact included the primary total knee construct sizing discrepancy, significant component deformation and early revision.Further impact could not be determined.No further medical assessment can be rendered at this time.A review of the production orders did not reveal a manufacturing abnormality that could have caused or contributed to the reported incident.A review of complaint history for the part numbers over the past 12 months and for the batch numbers based on historical data of the device did not reveal similar events for the listed device.A review of the instructions for use documents for knee systems reveal in warnings and precautions that the correct selection of the implant is extremely important.The appropriate type and size should be selected for patients with consideration of anatomical and biomechanical factors such as patient age and activity levels, weight, bone, and muscle conditions.Failure to use the optimum size component may result in a possible adverse effect.Higher rates of wear may shorten the useful life of the prosthesis, and lead to early revision surgery to replace the worn prosthetic components.A review of the risk management files revealed this failure mode was previously identified.The anticipated risk level is still adequate.A historical review concluded that there are no prior actions related to these products and event.At this time, we have no reason to suspect that the products failed to meet any specifications at the time of manufacture.The root cause of this event was determined to be wrong sizing combinations.Based on this investigation, the need for corrective action is not indicated.Should additional information be received, the complaint will be reopened.No further investigation is warranted for this complaint; however, we will continue to monitor for future complaints and investigate as necessary.We consider this investigation closed.H6: health effect - clinical code and health effect - impact code.
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